Lots of talk yesterday and I saw more this morning. So it's possible.
I agree it could well have a positive impact on us, but it could go either way! Finding out your previous manager has just been appointed moments before going on to the pitch could "get in their heads". There would also be the supposed impetus to the Fulham squad of trying to prove themselves in front of their new manager. It's one of those "psyche out" tactics that could backfire, though, as you say.
Pure speculation from me so it probably won't happen, but it would be interesting if they try it