it is not an assumption, you merely have to tally up axis wins and allies wins across games.
Slight favorite is not unstoppable. Also I seldom see allies win low luck global games without a bid, like once in a blue moon.
Also if you delete all ICs airbases and naval bases at the end of round 1, the total unit value between axis and allies is about even, allies just have an income advantage, but they are out of position.
At some point you have to match japan’s income with usa, unless you are doing the whole usa gets the carriers anzac gets the fighters… but there is a trick to beating that.
Also germany can’t wait past round 10 for russia. +19 from african NOs for russia means he will always make 10 inf, you get good odds rounds 7-9. buy tanks off minors and bombers off germany/west germany. blam hit it.
split income means split chances for axis to win europe VCs and pacific VCs. I am sorry but Japan comes through when germany can’t and vice versa in most games.
also usually germany doesn’t sink uk naval just presents the threat of doing so, sure if you got 5 transports and you give germany 75%+ he’ll sink it.
axis 55% win for dice games. 70% LL.