I don't claim to be a pilot but I highly doubt one needs to do a WWII dive bomb to create extra speed over max sustained level flight speed,,whatever that may be. All you really need to do is a casual decent to lessen the energy required to fight gravity, just like in a car. It goes faster downhill than on level ground. You need not drive over a cliff to see that effect. I'd also contend that any extra speed attained while in a decent could be at least be somewhat maintained during post decent level flight. No science to back that up just gut feelings on the matter. So, in essence the jackers wouldn't have been required to do some crazy stunt dive to reach those speeds. Also it seems at least one of the planes was banking to the left fairly hard upon impact disproving your conjecture the jackers would have done everything possible to maintain accurate flight steering. I think we should remember, even if one or both of the planes missed WTC a crash into the city itself might have been even more devastating as far as body count goes. Many people had a chance to escape the area after the crashes because the buildings were able to absorb the destruction of impact for some time. Lesser,older buildings in the area would not have fared so well and there would be no ground for the survivors to flee too. JMO Which video of flight 175 looks level to you? Pretty hard to offer analysis of anything when you don't know the angles between plane and camera.