I think the truth may be he's too Mexican. Dunno.
Interesting read, grain of salt:
it's easy to say in hindsight. considering BRAWN GP won the driver's championship at the helm of Ross Brawn, why wouldn't Schumacher be lured by what was seemingly a 'championship winning car' and his good old faithful technical director?
sure, he didn't win any grand prixs, but he hadn't lost much of his edge in racing. his current car has been stupidly unreliable. i would have liked to see him race for a couple more seasons.