why you think Davydenko can be a spoiler on any surface.
Davydenko should currently be accpeted as the fourth best in the world on clay and he likes aking the ball early, he has better chances than most to beat Nadal on clay (though still slim), see Rome, maybe the best match of the year. He is also probably as good as Federer on clay when he plays well, choked away what should've been a very close 5 setter at RG last year and turned into a straight sets win.
Hilarious that you should challenge his inclusion when he has such credentials and is a good player whereas Tsonga has shown nothing on clay as of yet and it is unlikely his game will suit. Plus Gasquet is nowhere near Davydenko as well.