I asked a few weeks ago about what people thought about him. He has no real record in GTs but taken in isolation his climbing performance at Mende + his ability in time trials suggest he could have some potential. Ok, so Mende is only 4km but at 10% it isnt one that a non-climber is going to win. However, we dont have any evidence that he will recover well enough to still be going well at the end of the tour, dont have any evidence for him doing well on stages with multiple mountains, or even one big mountain. These are all key to doing well at the tour. Had hoped the Dauphine would give some suggestions but he didnt do that well - then again the start of the tour is three weeks away and the final week is 5 weeks away, also not everyone who does well at the Tour does well at the Dauphine.
Last year it was autobusses all the way in the TdF but he may have had different aims or been trying to get into breaks on the flat stages. In the final TT he finished 17th on a lumpy course but was beaten by Andy Schleck. Might not have been that motivated i suppose and if he is climbing better now then he should be able to do better but to compare him to the surprise of the giro, thomas de Gendt, then de Gendt finished 4th in that time trial (after finishing 6th on alpe d'huez where Westra was in the autobus).
In short, if you are looking for someone to finish high up who has never finished that high up before, to do something like a Wiggins 2009, then he seems a good candidate. Not many would have thought that Vanendert would do as well as he did last year - i remember people laughing at me for suggesting he could make a select group of 30 on a climb yet he won one MTF and came second on another. However, it really is a big unknown. The performance of Poels and Ruijh will also have a bearing as they may be the team leader depending how things go. Personally, i think the best he could possibly do if everything went his way is come 10th, more likely around 20-30th, but given the unknowns he might only be capable of 80th.