I think his confidence has probably been on the floor for the last couple of years, when he has played its been for teams who are struggling, us, Fulham, Brighton etc. Since he's been at a team doing well, until their recent hiccup, he has shown some of his old form. Of course he's lost some of the pace he used to have but his instinct and knack for being in the right place is still there - by far his strongest asset, (I think his finishing isn't much better than just above average to be honest), but it is interesting to consider how a player can go from being written-off to someone worth re-evaluating once playing for a decent team doing well.
Gardner is not a too dissimilar case - struggled on-loan at struggling clubs, most people writing him off and saying how his serious injuries have finished any promise he had, then he goes to Forest who go on a fine run of which he's an integral part of and again we're all thinking how good he could be again.
If only all players with a question mark over them could get a loan spell at a high-flying team to give them the best chance of showing what they can do...though obviously its more impressive if they help that team's ascent, which in these two lad's cases, I think they have.