Tachikaze said:
Well, I see your point and I agree that is realistic, though for game purposes it is kind of disappointing really. This I say because you know in most games that the function of the unit is usually tightly connected with its name (for example: anti-tank squad is good against tanks, carriers carry stuff (planes), etc.) while the Garrison unit... Well, if it isn't the best for its intended job and not terribly cheap in manpower (which is one of your most scarce resources as Germany) then why build it? The only function I see for it now is like I said earlier, amphibious invasion defence and perhaps garrison for urban and really hard to get to mountain provinces that are for some reason important.
The garrison unit is the single best unit in the game for garrisoning an occupied province, keeping the locals in check via a permanent military presence, and providing a speed bump. Moreover, it is extremely cheap to produce compared to any substitute and consumes less supplies (and hence both cost you less IC on a daily basis for production of supplies but also less TC for distributing of supplies). A garrison unit is not a front-line defensive unit able to take on all comers or defeat an invasion alone, but then, I doubt that is part of the definition of a garrison. (Though it must be said - even a single mid-war [i.e. not the '18 crap] garrison in a coastal province has excellent chances against a small non-Marine landing party due to the very substantial amphibious assault penalties). On the other hand, for Germany, with its surfeit of IC and comparatively (compared to your goals

) low manpower, I can see why you are disinclined to build garrisons and would rather build infantry instead so long as your conquests remain fairly small, such that you can easily switch from defensive to offensive operations as your needs demand.
And then again, it must be stated that I am very biased on the topic of garrisons. Just like you are likely to hear Johan advocating airpower given the least opportunity, and more than a few beat the drums for panzers, and a couple of wanna-be admirals consider the navy to be the premiere force, I am the resident infantry proponent... My current personal record (not as Germany, admittedly) is 120 garrison divisions. 60 (the same resource cost) or 120 (the same manpower cost) infantry divisions would not fulfill their job half as well.
To answer another of your questions regarding garrisons, in order to move them to different land-masses (i.e. no direct SRD) you load them on to transports, sail to the land-mass in question braving the dangers of enemy navies on the high seas, and unload them (sea transport), then SRD them to whereever you want to go, just like with any other land unit.