I don't see how. . . .if you are dehydrated and taking more water out of the system. . .how can you possibly feel better?
Plus, there is still a degree of alcohol floating in the system that still has an impact on the nervous system, which can cause lack of balance and coordination. You also run the risk of blacking out, which poses as a dangerous situation.
Personally, I would rather train at 100 percent when the body is 100 percent healthy. The body is already under immense stress because it is trying to recover from poison that has entered and polluted the system.