Valentino Rossi's latest poor performance, a seventh place finish in the Czech Republic Grand Prix, has dropped the Italian a massive 60 points behind Casey Stoner with six rounds of the 2007 MotoGP World Championship remaining.

So what exactly has gone wrong for Rossi this season? It's an easy question to ask, but one that generates heated debate - as illustrated by some of the viewer comments left on

"Rossi and crew have a very short memory. At the beginning of the season they were confident and happy because this season the Yamaha package was "perfect". Now everyone is beating him the package is at fault, not him." Ian A Bedford

"Go on then explain to me, if Rossi has 'lost it', 'had his day' etc.. WHY IS HE SECOND IN THE CHAMPIONSHIP????!!!!! 18 other riders on the grid would kill to be where he is..." Morphine

"He was on the same tyres for ages, now there are some new and better riders, all of a sudden he blames his tyres. I think he's lost it, once again, time to retire." Jeff van Hoesel.

So has Rossi really 'lost it'? He certainly made one big mistake by crashing out of the German Grand Prix, but has also won three races, second only to Stoner's seven victories. The top speeds charts indicate that Rossi's Yamaha is still down on power relative to Stoner's Ducati, but how significant is that deficit? Meanwhile, Rossi has frequently cited a lack of grip from his Michelin tyres compared to Stoner's Bridgestones, but why has Rossi been beaten by other Michelin riders at four of the eleven races he's finished this year...?

Who, or what, do you think is to blame for Rossi's poor performances this year?