From: Zagreb, Croatia
Commerce raiders were not only to sink enemy shipping but also forcing the enemy to use many of its naval ships to search for them and to escort convoys.
Vs subs you just need a lot of DDs and smaller vessels to escort convoys, vs large ships you either need lots of cruisers or a battleship with limited amount of cruisers
I would argue that building 4 BBs was too few to challenge any power and at the same time way too many for simple "fleet in being". Just Scharnhost + Gneisenau would had done it.
But this of course with the benefit of foresight
Of course the Germans did not specifically build 4 capital ships for either purpose. These ships were part of a general naval re-armament plan, and later the repudiation of the Treaty of Versailles with the implementation of the Anglo-German Naval Agreement.
Hitler believed that Britain could be placated and he wasn't going to make the same 'mistake' as the Kaiser and threaten Britain's naval dominance and provoke her to war.
When it became clear the Britain was not going to play ball the fanciful Plan Z came into being. Raeder was told there would be no general war until 1944. But events took a different path, Hitler could not wait, and the British and French drew a line in the sand at Poland.
Thus the Germans went to war with what they had, not what they planned to have. As for the war, the surface fleet were pretty unsuccessful in terms of tonnage sunk, but they did achieve results as a fleet in being and the Admiralty felt forced to keep capital ships at Scapa to cover off this menace. This was a god-send for the Regia Marina.
Ahh... Italians in the Med...
BTW, with what we know nowadays, it seems that Germans (with the Enigma) "helped" the Royal Navy much more than the Regia Marina... God knows how things would turn if Bletchley Park was not involved...
Prior Preparation & Planning Prevents Pathetically Poor Performance!
A & B: WitW, WitE, WbtS, GGWaW, GGWaW2-AWD, HttR, CotA, BftB, CF
P: UV, WitP, WitP-AE