SC has tried to handle it with a 2-level approach - using both high strategic and tactical concepts, and it fails (again IMO)
Convoys are handled at a high strategic level - there are convoy routes, they convey a certain amount of resource each turn from 1 end to the other, and U-boats used against them cut down the resources delivered. So far so goo.
But the U-boats are tactical units, as are the warships sent against them - you can't actually escort convoys - you have to use your warship units to move along the convoy routes looking for individual u-boat units to attack! Bah humbug!
Similarly land units being transfered by sea become distict naval units, and are fairly easy to sink if you can catch them.
I was reading up on the Scharnhorst & Gneisenau's atlantic foray last night - They were ineffective againat most convoys because the Brits were putting a 15" gunned battleship with many of them!! They sank some 25-ish ships, but this was a poor return for the resources expended in the voyage, so I would like to see some resource expenditure required for such operations rather than the simplistic model most games assume that a unit just gets to move without any furtehr consideration once it is built.
So the Atlantic commerce war needs to have a submarine and an escort component - again referring to Hitler's War this as very simply handled - the allies bought ASW points, the Germans bought U-boat points. ASW points attacked the U-boat points in an ocean and inflicted losses. U-boats then attacked the resource points being shipped through that ocean (see my thread on off-map resources) and inflicted losses on them (or maybe the U-boats got to shoot 1st - I don't recall).
In a sophisticated computer game I'd expect to be able to shift U-boats between a convoy raiding force pool and a "tactical" fleet force pool that might be used to attack naval targets rather than commerce.
also I'd like to see the allied submarine forces given some presence in the game - attacking Axis supply routes to Nth Africa, and convoys from Norway - even the Soviets trying to attack commerce between Sweden and Germany.
