But they only reduce supply so just cover one rail and no problem.
However personally I don't like the partisan rules. At this level there just need to be some garrison requirement, when met then no problem. To avoid all or nothing some attacks should occur even if garrison is met but only in late war.
Garrison rules would be much better. Without garrisons in place supply takes the hit. Just to show how out of whack partisans are at this scale "By the end of 1941, more than 2,000 partisan detachments (with more than 90,000 personnel) operated in German-occupied territories". Obviously as the war went on, this number increased.
But what this represents are units representing about 45 people per partisan group across all of Russia (90,000/2,000) So for these groups to have any real impact on a game of this scale is really not realistic. Just because most WWII games have partisans does not mean all of them should.
Only in Yugoslavia did the numbers get big enough to really impact a game of this scale. And then not until late in the war. "By late 1944, the total forces of the Partisans numbered 650,000 men and women organized in four field armies and 52 divisions, which engaged in conventional warfare. By April 1945, the Partisans numbered over 800,000"
A much better way (and maybe even easier from a programing point of view) would be to just reduce the amount or resources by X from Yugoslavia/Russia unless Y garrison is met. For both countries, the Axis would need to greatly increase their 'garrison' troops over the historical record since over the course of the war:
"The Soviet partisan activities was a strategic factor in the defeat of the German forces on the Soviet-German front. During the summer and autumn of 1942, when partisan warfare did not reach its highest peak, the German Army devoted about 10 percent of its overall strength in fighting partisans, including 15 regular and security divisions and 144 security and police battalions. At the same time, the total strength of German and Italian forces in North Africa was 12 divisions. The partisans made significant contributions to the war effort by interrupting German plans to exploit Soviet territories economically. German forces obtained only one-seventh of what they looted from other European countries. While about $1 billion worth of food and other products were expropriated from Soviet territories by the Germans, more than $26 billion worth of goods and services were extracted from other European countries."
Another thought would be to just have a production line item to 'produce' partisan points(?) since some effort was made to supply them from the actual war production. Then you could produce 'anti-partisans' points(?). With some ratio of partisan points to anti points determining supplies/resources reduction (or lack thereof)
Just some thoughts on different ways to handle this topic that fit the historical record a little better.
Bottom line is I'd much rather have partisans abstracted versus the way they are handled now.