Although I have had the following spreadsheets finished for some time, I wanted to get some new experience playing the Germans before commenting much on the Nazi-Soviet pact and the possibilities of breaking it in WiF, since my last several games have been as all or part of the Allies. I am now in the midst of a new game which has reached Jul/Aug '40 and I am more ready to fine tune these numbers.
An analysis of Russia's possibilities to 'stuff' the border depends on projected build plans for Germany and Russia. Of the two, Germany's is subject to more variables so I will start with that. The important optionals for this analysis include playing with Pilots, City-Based Volunteers, and Rules as Written 13.5.1 Oil, Option #48.
A big variable in breaking a Pact is the chits; all that can really be done here is to compute the average value of each chit as the turns move along and go with that. Perhaps there is a better analysis than that possible with statistical methods but I wouldn't know.
For purposes purely of creating Garrison points, some unit types are more efficient than others. Anything that creates one point for two BP is the best - MIL, GARR, MTN and Pilots; MECH at 2.5 BP/garrison point are next, followed by INF and ARM at 3/point. Yet some compromises have to be made from pure garrison efficiency. Both Germany and Russia start the game with 5 planes in the Reserve Pool and could thus add 5 garrison points by building 5 pilots. Although it wouldn't be a very good use of BPs, this possibility is part of the German analysis, but it is somewhat more feasible for the Russians. For the German build plan, this also has to create a force realistically capable of taking on the Russians, so it includes building both the Guderian and Rommel HQ-A's even though they are not 'garrison efficient' units; it also must be a build plan ready to take advantage of a Russian strategy that is not stuffing the border, so the long building armored forces must be built before the infantry. Another very desirable German unit for Barbarossa, the motorized '6th Pz' Engineers at 3 BP for .5 garrison is skipped, but all available MECH and ARM corps are built. By the fall of 1940, this build plan has built out the above mentioned pools, including the INF, so a few Mech divisions are built to give extra punch to the 2d10 tactics I prefer using, and to prepare the gearing limits for an important build of the new force pool additions in J/F '41. After that the plan abandons building for the sake of garrison points only as anything built in M/A '41 won't arrive in time to influence the garrison totals in the summer of 1941, which is when the Germans want to break the pact, however I left in some sample 1941 builds to illustrate what has not been built thus far.
The German build plan has to make some basic assumptions on what is happening in the game in order to think about how many BPs can be spent each turn. So I went with the vanilla assumption that Poland falls in S/O '39, and then nothing much else happens until M/J '40; in particular there are no political decisions made in the Balkans. A German 'No Bessarabia' decision (attacking Yugoslavia on impulse 3) can dramatically boost their economy through the addition of aligned factories and additional captured resources (although by also slightly increasing the Russian economy). However I stick with spending 14-15 BPs a turn through the end of 1940, despite probable captures of resources in the Low Countries and France in the summer of 40. You will notice that the plan includes building 5 new pilots in 1940 yet only one plane, which would make for a very antiquated Luftwaffe and takes no account for losses. So let's assume that any BPs available over the 116 spent in this plan through the end of 1940 get used to build a few new airplanes.
Here is the German plan and resulting maximum possible garrison points:
S/O 39 Reinforcements = at-start units = 53.5 garrison points
Chits = 0; avg value = 0; Max Garrison = 54
Builds = HQ-A, 3 MIL = 14 BP (+Vienna SS MIL free)
N/D 39 Reinforcements = 3 MIL, Vienna SS MIL, SS INF, Pilot, Armdiv, Gun = 9 garrison points
Chits = 2; avg value = 2.33; total value = 4.66 Max Garrison = 67
Builds = ARM, MECH, 2 MIL = 15 BP
J/F 40 Reinforcements = 2 MIL = 2 garrison points
Chits = 2; avg value = 2.33; total value = 9.32 Max Garrison = 74
Builds = ARM, MECH, 2 MIL = 15 BP
M/A 40 Reinforcements = 2 MIL, PARA = 3 garrison points
Chits = 2; avg value = 1.91; total value = 13.14 Max Garrison = 81
Builds = ARM, MECH, MIL, Pilot = 15 BP
M/J 40 Reinforcements = HQ-A, MECH, MIL = 5 garrison points
Chits = 2; avg value = 1.91; total value = 16.96 Max Garrison = 89
Builds = HQ-A, MTN, 2 Pilot = 16 BP (+Amsterdam SS GARR free)
J/A 40 Reinforcements = ARM, MECH = 4 garrison points
Chits = 2; avg value = 1.91; total value = 20.78 Max Garrison = 97
Builds = MECH, MIL, GARR, 2 Pilot = 13 BP (+Paris SS MIL free)
S/O 40 Reinforcements = ARM, MECH, MIL, Pilot, SS GARR, SS MIL = 10 garrison points
Chits = 2; avg value = 1.91; total value = 24.60 Max Garrison = 111
Builds = 3 INF, Mech division, LND-2 = 14 BP
N/D 40 Reinforcements = ARM, MTN, GARR, 2 Pilots = 7 garrison points
Chits = 2; avg value = 1.91; total value = 28.4 Max Garrison = 122
Builds = 3 INF, 2 Mech division = 14 BP
J/F 41 Reinforcements = HQ-A, MECH, 3 INF, 2 Pilot = 9 garrison points
Chits = 2; avg value = 1.91; total value = 32.24 Max Garrison = 135
Builds = HQ-A, ARM, MECH, 2 INF, GARR = 27 BP
M/A 41 Reinforcements = 3 INF, Mech division = 3.5 garrison points
Chits = 2; avg value = 2.26; total value = 36.76 Max Garrison = 143
Builds = MECH, Offensive Chit, LND-3, SUB, MOT = 28 BP
M/J 41 Reinforcements = 2 INF, GARR, 2 Mech divisions = 4 garrison points
Chits = 2; avg value = 2.26; total value = 41.28 Max Garrison = 151
Builds = LND-2, FTR-2, 2 MOT, 2 SUB, Pilot, Gun, Armor division = 24~26 BP
J/A 41 Reinforcements = MECH = 2 garrison points
Chits = 2; avg value = 2.26; total value = 45.80 Max Garrison = 158
Builds = LND-3, LND-2, FTR-2, 2 Pilot, 3 SUB, 3 MOT = 26 BP
S/O 41 Reinforcements = HQ-A, ARM, MECH, MOT, Offensive Chit = 7 garrison points
Chits = 2; avg value = 2.26; total value = 50.32 Max Garrison = 169
You will soon notice that this is a theoretical garrison total only, since it puts EVERYTHING on the Eastern Front to generate garrison points, leaving nothing to help Italy in the Med, no BPs for even one U-Boat to pressure the Commonwealth, assumes ZERO losses in combat, and most glaring, doesn't include any garrison units in France! These completely unrealistic assumptions are necessary once you start to see the garrison numbers the Russians can generate, in a far more realistic fashion. One last wildcard is the addition of the Axis minor allies in the Balkans, but since these can only be activated by messing around in the land of Tito, this may or may not produce very much of a net gain in garrison available for the Soviet border zone.
The Russian build plan also needs some basic assumptions made, albeit fewer than the German one, are also easier decisions to make during the game, and, in my opinion, result in the best Russian strategy anyway. The basic one is that Russia does nothing outside of her own borders. No conquest of Iraq nor Persia, no meddling in Balkan affairs, and definitely no war with Japan. In my opinion none of these are worth delaying the entry of 'Uncle Sugar' and his pipelines of goodies that can be vital during an all-out Barbarossa campaign, activated by entry options 19 & 30, not to mention the Allies' long-term prospects tied to the timing of US War Appropriations. I've long thought too many players just simply get bored playing Russia and launch foreign adventures out of boredom more than anything else. The Pacific need not be completely emptied until the beginning of '41 and after that this plan could allow the Japanese to cause some economic damage of course, which is not for the faint of heart. As for the Balkans, the easiest and safest place to 'stuff' the border is in southwest Ukraine, so if this is your goal you are better off not demanding Bessarabia, hoping the Germans activate it themselves via attacking Yugoslavia — though you may want to threaten to do this, and you might as well deploy for it.
I think this is a very good Russian build plan to prepare for a 1941 Barbarossa in general, although I like to alter it slightly to add a few Forts here and there, but then I'm not afraid of a '41 Barbarossa and I might use this build plan to sucker in the Axis to their doomed historical strategy by not stuffing the border at all. It does purchase a few extras such as the Ski divisions for use in Leningrad, as well as a Mountain division for the same purpose, but at the expense of skipping the Red Air Force's FTR development program. Also note that the total garrison number could be increased slightly by building 5 Pilots as the German plan does, but planes aren't all that useful for the Russians in 1941, so that idea is not included. I also can't quite bring myself to go all-out on this plan and leave one good unit in Leningrad as well, though that is not reflected in the Max #. Here are the Russian numbers:
S/O 39 Reinforcements = at-start units = 23.5 garrison points
Chits = 0; avg value = 0; Max Garrison = 24
Builds = ARM, GARR = 8 BP
N/D 39 Reinforcements = - = 0 garrison points
Chits = 1; avg value = 2.33; total value = 2.33 Max Garrison = 26
Builds = ARM, GARR = 8 BP
J/F 40 Reinforcements = GARR = 1 garrison point
Chits = 1; avg value = 2.33; total value = 4.66 Max Garrison = 29
Builds = ARM, MECH, INF = 14 BP
M/A 40 Reinforcements = GARR = 1 garrison point
Chits = 1; avg value = 1.91; total value = 6.57 Max Garrison = 32
Builds = MECH, MTN, GARR, CAV = 13 BP, save 1 = 14 BP
M/J 40 Reinforcements = ARM, INF = 3 garrison points
Chits = 1; avg value = 1.91; total value = 8.48 Max Garrison = 37
Builds = 2 INF, GARR, save 6 = 14 BP (7 total saved)
J/A 40 Reinforcements = ARM, MECH, GARR = 5 garrison points
Chits = 1; avg value = 1.91; total value = 10.39 Max Garrison = 44
Builds = 4 INF, save 2 = 14 BP (9 total saved)
S/O 40 Reinforcements = ARM, MECH, MTN, GARR, 2 INF, CAV = 10 garrison points
Chits = 1; avg value = 1.91; total value = 12.30 Max Garrison = 56
Builds = 5 INF = 15 BP (use 1 saved, 8 total saved left)
N/D 40 Reinforcements = 4 INF = 4 garrison points
Chits = 1; avg value = 1.91; total value = 14.21 Max Garrison = 62
Builds = HQ-I, INF, Ski division, Mtn division, save 2 = 14 BP (10 total saved)
J/F 41 Reinforcements = 5 INF = 5 garrison points
Chits = 1; avg value = 1.91; total value = 16.12 Max Garrison = 69
Builds = MECH, HQ-I, 2 INF, GARR, Engineer, 2 Tankers = 23 BP (use 9 saved, 1 total saved left)
M/A 41 Reinforcements = INF = 1 garrison point
Chits = 1; avg value = 2.26; total value = 18.38 Max Garrison = 72
Builds = ARM, Ski division, Advance build GARR, 2 Tankers = 14 BP (1 total saved left)
M/J 41 Reinforcements = HQ-I, 2 INF, GARR, Ski div, Mtn div = 5 garrison points
Chits = 1; avg value = 2.26; total value = 20.64 Max Garrison = 79
Builds = gun, pilot, aircraft, save, etc.
J/A 41 Reinforcements = HQ-I, MECH = 3 garrison points
Chits = 1; avg value = 2.26; total value = 22.90 Max Garrison = 84
Builds = 2 guns, 2 pilots, 2 aircraft, etc.
S/O 41 Reinforcements = GARR, Ski = 1.5 garrison points
Chits = 1; avg value = 2.26; total value = 25.1 Max Garrison = 88
So in summary it is my opinion that the Russians can prevent a Summer 1941 Barbarossa if they so desire. By the late fall of 1941 this begins to be in doubt, but by then the point is moot. Even without becoming an active major power via a DoW on Italy or Japan, the Russians can retreat somewhat safely via combineds under the cover of General Mud and proper rearguard ZoCs; nor do the Germans have much incentive to occupy any Russian home country hexes in such weather, inflating Russian production. It is even easier to retreat from the Ukraine if the Germans have activated Rumania early.
Well there you have it. I have worked these plans out over several years; in the winter I run a business that consumes 80+ hours a week and the only way I can participate in WiF is either through this forum (thank y'all very much for putting up with me) or through theoretical exercises such as this one. The chit values do reflect the current entry chits on CS 24 ©2007, and I'm fairly sure I have the correct amount of corps units in the German and Russian force pools (perhaps the German Mech division pool is slightly different with the new Mech in Flames sheet). If you can find any mistake in these build plans please let me know right away. Whether to stuff the border is up to each Russian player, but it is definitely a viable choice.