Interesting. I've always thought that Grosjean was a very up and down player anyway, simply by the style of game he plays - flashes of brilliance and periods of ineptitude in equal measure.
I think he's one of those confidence players; when he gots on a roll like he did towards the end of 2001, when he beat Haas in Paris, then Rafter, Agassi and Kafelnikov to reach the Masters Cup final he was practically unbeatable, but when he had to defend all those AO points at the start of 2002 the pressure got to him.
Added to that, of course, is the fact that he's undeniably the biggest choker in the game. That infamous AO semi against Clement was practically repeated at last year's US Open when they met in the second round; Grosjean led two sets to one, then led with a break at 4-3 in the final set before practically conceding the last three games of the match (on match point he casually knocked a backhand volley almost into the back fence...).
Who, of course, could forget the Moya debacle in Paris - again, one decent volley could have settled the whole thing, but...?
It's quite ironic that as the clear French no. 1, he's a pigeon for every other French player - in particular Santoro and Clement, who it seems can almost beat him at will.
Having said that, he looks to be in good form at the start of 2003 and I think he'll make something of a resurgence, especially at Roland Garros.