It's hard to argure that after Laguna 08, Rossi had not gotten into Casey's head. That was the moment he turned his season around, and Stoner started to make unforced errors. Fact. Yes, we all know now that Stoner was doing a ....... awesome job on the Ducati, (I hate saying that, not because of disrespect for Stoner but because a number of PS users get a semi when they read those words) but at that point, Rossi had him beaten. Just for the rcord, Rossi won the title that year, so to clarify that, yes, he beat him.
I don't see how rossi or probably anyone else could have ridden better in 2008 than he did, and I think his championship was substantially attributable to that.
I thought at the time stoner's crashes in the 2 races after laguna seca 2008 could reasonably be attributed to pressure, although stoner claimed that the bike had given way for no apparent reason, not inconsistent with claims by him and other ducati riders including rossi in later years, although thus did not seem to recur in the rest of 2008 or 2009. You find problems with the semantic abilities of some, but you should also remember that mathematics came into it in 2008. Someone (not me) said after laguna seca and before the crashes in the 2 subsequent races that stoner's chance was basically gone after laguna seca. If you recall dani and jorge were both either banged up or absent, and hence rossi was likely to come second in any race stoner managed to win (he in fact managed 1st or second in every remaining race except for the one where he had the practice crash and finished 3rd). Stoner hence with a 25 point deficit needed to win 5 of 7 races in which case he would have finished equal in points and won on the basis of more wins, If crumbling to pressure cost him the championship it was putting it in the sand at laguna seca.
What was inconsistent and unjust imo was attribution of stoner's scaphoid injury to imagination and invention and similarly his 2009 illness, by the same people quick to (correctly) point out that rossi's 2010 season was heavily affected by injury.