From: Seoul, Korea
One of the reasons I play the AI is that I can do 20-minute turns and not watch the combat replay. I do other things on my other computer while the turn is processing. Playing Downfall I wouldn't even read the inevitably huge combat report; just look for anomalies in "ships sunk" and "aircraft losses" and only dig into the combat report when necessary.
I figure with my personality (don't remember my 4 letters from Meyers-Briggs, it's been a while, but I do remember the word "perfectionist" from somewhere), I would bog down to 2-3 or more hours per turn vs. a human, and I don't have that kind of time. Plus, I'd be thinking about the game all day instead of thinking about work. But that's just me.
In terms of time savers, you can fiddle with pilot training once a month or whatever works for you, rather than every day. I also put my subs on auto. I figure the AI needs all the help it can get.
Beer, because barley makes lousy bread.