As the axis player I follow the axiom of moving and using the Luftwaffe in total (if at all possible) to support all European invasions/operations prior to Barbarossa in 1941. And for this and a Greek invasion I'm a big believer in also using all available naval assets (i.e., warships and subs) to support the operations. My philosophy for these such operations is that's it's better to be woefully over prepared and over strength if the allied played does NOT react in strength than the opposite. That is, woefully under-prepared and under strength for a very strong allied response to such. Simply put, "better safe than sorry."
Through repeated play I typically know how a number of my opponents will respond to such operation; but still I don't assume anything. I always play it straight up against them, as I would against a "unfamiliar" opponent, and move my air and, if applicable my naval, units in total in order to be in position to counter any strong allied response.
By the way, moving the Luftwaffe in total to support such operations is highly historical. For me it's gratifying when tactics that makes a lot of sense game-wise are also historical.
Believe when I say you don't want to get caught with your pants down by skimping on naval and air support for such an operation only to find that your opponent has moved in strength into Norway and against your invasion forces. However; I've found the converse to be quite gratifying. That is, being able ambush and to inflict significant losses on the RN and / or French navy and on any of their transports moved to reinforce Norway. I once had one of my Canadian opponents call me a B@$T@RD, all in good fun, after I sank the 1st and 2nd Canadians on transport trying to reinforce Norway under such conditions. That response still gives me a chuckle when I think about it today.
