Well, the player in question is a bit stubborn, but I'm glad I'm not the only one who sees the advantage in evaluating past moves with AI-aid.

I don't know what to think of using a 'passive' board to look at your moves... In other games (hex/twixt/go) it's accepted. But the lookahead is what's so hard with reversi, and using a viewer for you lookahead makes it a alot easier (and gives a huge advantage in the endgame). I'm not sure where I stand in this, but I would definately prefer a player who doesn't use a passive board.