MANDABOLE,
I tried exactly what you suggested a week or so ago. The convergence is adjusted automatically by range. Funny, I even shot at the ground in a B17 at different heights and the hit pattern seemed to be similar regardless of how far it was away (until I was too far to see anymore). It was more like the guns on a P-38 that the ones that are mounted as far apart on a bomber as they are.
Bomber guns are a pretty tough topic since I think there are lots of ways to look at it. A 1 on 1 with a bomber is far more dangerous in AH than the stories seem to indicate in WW2. I take that as a gameplay concession since solo bombers would get shot down the second they encountered an enemy fighter otherwise. The gunnery is deadly, even a good attack can end up as death to a fair gunner, a good gunner will eat you up unless you make a perfect attack, and even then you run the risk of serious damage. 2 on 1 against a bomber, the bomber doesn't have much of a hope of the two guys coordinate their attack properly, and that's equally unfair the other way. I mean, once a gun is turned one way to fire at an enemy, all the guns seem to turn that way, and thus to swing the gun around 180deg to fend off a second con is almost impossible.
I put a lot of this "overpowering" gun thing down to the fact that you are almost always facing at least 4 guns when you are attacking a bomber, it's like facing a slightly improved (since HT has said they are slightly improved .50's) P51 attack, where the convergence is always adjusting. No wonder it is so tough. I'd hate to be at convergence for long against a P-51 so it's no doubt it is bad news to attack a B-17.
I hate attacking bombers, myself, thought I do it all the time since it is often really important in defense. I try to set up the attack as best possible but it's not always practical or possible to do so. Bombers over 25K in alt have the added advantage that the current fighters are 'mushy' in handling at that alt so setting up an attack is even more difficult.
I don't know what the real answer should be, but this is my view of it. I know I feel really uncomfortable attacking bombers solo, but feel fine attacking them in pairs. Amazing the difference is really just that you know the gunner can only shoot at one of you and not the other. It seems to be inversely fair for bombers based on whether you encounter one plane or two... 1 on 1 the bomber has a huge edge, 2 on 1 the bomber is at a huge disadvantage.
-Soda