I'll probably get slaughtered here, but I wouldn't be surprised if there was some truth to it either. His attitude towards teammates seems to have changed in the past couple years. The supposed quotes themselves were most likely made up but we've all seen him getting frustrated/yelling at his teammates & not really in the same way that Puyol might.
No question Messi can get annoyed on the pitch, but seeing Alexis wasting good chances Messi created for him would make anyone want to slaughter him. We all know neither Pedro nor Alexis are an equal match for Messi and I sometimes feel Messi, and now Neymar and Messi, deserve a better partner (I'm dreaming of Reus).
But it's one thing to get annoyed on the pitch and another to harass others off the pitch, and I see no indication whatsoever that Messi would do that. On the contrary. Messi bitching around and Puyi, Xavi etc keeping quiet about it? No team can function if there are hard feelings or ongoing feuds among the players - see Bayern, who only excelled after Jupp sorted out the feuds. Same goes for Barcelona. And it always seemed to me that Messi is getting along well with everyone, especially Cesc, Pique, Iniesta etc.
Thing is, also, there have been more occasions where Messi could have finished himself but passed to other players to let them give it a try than there have been incidents of Messi shouting at others (Villa). Plus, Messi always, always almost immediately thanks and celebrates with whomever gave him the assist. And he usually tries to involve others in his play instead of just doing everything on his own.
I know these arguments are somewhat lame and don't prove anything, but this is exactly why this story is quite clever - no one can say anything against it since all we see is his behavior on the pitch. No one knows what happens off the pitch except for the players, and they are allegedly forced to keep quiet about Messi the bully.
