I think taking and holding CAU in G2 can be a viable strategy.
Russia often stacks CAU but without enough people to hold it against a determined (or slightly lucky) attack, and then lacks a counter-strike force.
The goal is to take CAU with 1-2 armor. Russia can only counterattack with 2-3 infantry.
Then Japan has to either take Persia out, and/or land 4-5 fighters in CAU for defense against the UK.
If Germany holds CAU, it can build 4 units/turn (vs Moscow building 6/turn) and with some reinforcements it should be able to hold it for the rest of the game, while getting all three NOs. It should make it very easy for the Axis to win.
Take 1
You can see this game where I tried it and failed. Russia held on to CAU with a single bomber (a lucky bomber that hit twice on defense!). I had about 68% chance of winning the battle and figured that at least he’d be forced to take the bomber casualty to increase his chances (but he didn’t).
http://www.axisandallies.org/forums/index.php?topic=16771.new#new
Take 2
I’m considering using this strategy a second time against A44BigDog
http://www.axisandallies.org/forums/index.php?topic=16764.new#new
Italians suicide amphibious assault it - hopefully kill 2 units (cru, bat shell + inf and art).
Germans hit it with everything. Have about 85% chance of holding it with 2 arms. Then you’ve got only 2 russian infantry to counter attack (10% odds for you).
Then before UK hits, Japan can strike PER and land 3-5 fighters in CAU.
Downsides: risky. You neglect Africa and other places.
Waiting to rush Russia with a stack of armor positioned in EPL, using the Italians to open up a path to CAU, KAR, or MOS on G3 or G4 might be a much better strategy.