I think that the Sea Lion thing is there to represent the threat so that the UK doesn’t go on offense right away.
If you don’t play it conservative… if you don’t buy all infantry the first turn… if you go all in on the Italian fleet… you’re gonna lose the UK.
For example… if you’re building naval units and bringing up the carrier from Gibraltar… you’re not attacking the Italian fleet. If you’re buying all infantry… you’re not threatening Africa or Norway at all.
My point is the Germany doesn’t have to decide if it’s going Sea Lion or Barbarossa until it’s Turn 2 Purchase Units phase. That means that either way, turn 1 the UK has got to play it safe.