I will not rule out a career slam, but I still think that in order to win Roland Garros he will need a VERY favourable draw (Andre, is that you?), with some of the top contendors losing early etc etc...
There are about half a dozen in Spain alone who would take him out in 5 on clay...
Corretja for example, has a good record against Hewitt as it is. If they played at ROland Garros, I would put good money on Alex. Past his prime or not.
In 2001 Ferrero made mince meat out of Hewitt - and NO Hewitt was not number one then and is far better now - but um, so is Ferrero. (it's also worth noting that Canas had him by the ropes in 2001 and should have by all means won, but ran out of steam).
I don't think that I even need to go into the possibility of he playing MOya at Roland Garros....
If Guga comes back healthy - YES Hewitt beat him on clay in Brazil, but Hewitt is a different player when he plays for this country and Guga is when he plays are ROland Garros...
Bascially in order for Hewitt to win the French Open he will need one hell of a draw, a couple injuries, and a choke or two.