Oh he's certainly one of the best ever. I'd never dispute that. I can't really name anybody else on the grid capable of seriously going against Lewis over the course of a season.

But the Red Bull has went from the most dominant car ever to second best, with the Mercedes in a not too far behind 3rd (certainly good enough to compete depending on the track)

Max has stated that the car now needs his complete concentration otherwise it's easy to lose control, whereas last season and early this season it was on rails and just did what you wanted it to do.

I think that if he was tired (and I know I would be if I stayed up doing competitive sim-racing past 2 in the morning!), it'd be a lot more noticeable in his current car than in last year's (or early season this year's) car, because he has to be more "on the limit", so-to-speak, in order to get a good result.