Reactor questions

Gravity tech. We know the Minbari and Centauri have it. We know that they are the top dogs (except for first ones) in the B5 universe? Could there be a connection:

1. Would the use of anti-gravity as opposed to magnetic bottling lead to a stellar (pardon the pun) increase in the efficiency of a fusion reactor?

2. If yes, would this hypothetical increase in efficiency be teh explanation for the Minbari and Centauri dominance militarily? Literally, on a pound-for-pund basis, do their ships produce enormous amounts of power?

3. If the Minbari are using antigrav tech for their reactors, could that explain the Black Star? Could the EMP from the nuke have fried the control leads for the fusion reactor (some bonehead had the access panel off, or just a golden BB), touching off the explosion that actually destroyed the ship?