Constantly flip-flopped? He flip-flopped #1 time.
Revan has no conviction in the force? Sounds like speculation.
Flip-flopped may be the wrong word, but he does lack conviction. He sacrifices Jedi teachings during the Mandalorian Wars for victory. Other generations of Jedi in his position would not. The truly powerful will protect all lives, not just the important ones. Revan sacrificed worlds for victory. Other Jedi would have devised a strategy that would gain victory, but save the most lives.