I agree, an 8VC game is almost always an Axis win, and usually an easy win.
I believe its key for the Allies to put pressure on both theaters in a “short game”. The US can put a lot more pressure on the Axis in the Pacific in an 8VC game than they can in any other type of victory condition. If the UK can slow the Japanese with a factory in India, buying time for the US to take the Philippines, and if Russia and UK can put enough pressure on Germany to keep Leningrad the Allies can win, but it’s usually an easy win for the Axis.
The Allies can do it, it’s just a lot harder for the Allies to win an 8 VC game because they don’t have the time they need to get their “war machine” fully flowing.
“Short games” favor the Axis; “Long games” favor the Allies. I think the Germans believed this also, that’s why they developed the blitzkrieg, they new they had to take over their objectives quick because they believed they could not survive a “long war”.
I’m pretty sure that is why most tournament games are played with and “open bid”. With an open bid, the bid can be “awarded’ to either the Axis or the Allies. In a short game, the Allies should want the bid to help level the field, in a long game, the Axis should want the bid to help level the field. That’s how I understand an “open bid”, its tool for “leveling the odds” depending on the length/type of the game/victory conditions.
That’s why to large degree I still favor the “IPC victory condition” of the classic game Most tournaments still use this to determine winners if the 9 VC is not achieved in so many hours/rounds because it is an easy way to see who is “winning’. I think everyone would agree, regardless of who controls some of the victory cities that the Side that is making the most IPC every round is going to win. If you make more IPC, you make more units, more units is always better than less units.