Someone with knowledge please fill in, I keep hearing about him failing out with players, is there truth to that?
Not with the ones that are disciplined and hard workers... Not with the team workers.
OK - he had his clash with Ibrahimovic when he was at Ajax. He really asked him to work for the team etc. - and Ibra did not really like it. Van Gaal (who was not a coach there but the technical director) sold him to Juve. He is part of Ibra's book. But I think that story just shows the differences between van Gaal and Guardiola. Both could not live with a player like Ibra - van Gaal looked for the confrontation, Guardiola shied out of it. I think the first method is better. As a player you know the situation like this and you can react.
He has his special ideas. And he talks with the players openly. He is nobody for the maybes. Some can take it - some just cannot. Some might still have illusions and think that it might change.
As a Bayern fan and you look back - even if some of his decisions regarding players was controversial - he actually was right even if some where hard to chew at that time.
The story with van Bommel is just an example for that. Van Bommel then was the Bayern captain and the middle of the dressing room. But he was not showing form on the pitch - and you already saw that he somewhen will really be a liability. Van Gaal saw Kroos' future in central midfield (that is actually where he is playing with Guardiola, too) and he got Gustavo in winter 2011. He just could not give van Bommel the starting guarantee and role he had before. Both - van Gaal and van Bommel - had a short fight with the result that van Bommel left for Milan. Looking back it was a blessing that that transition happened like it did even if it added to the failures of that season. But it was the right time to change that and make Lahm and Schweinsteiger the captains. And it was better like this than to have a unsatisfied van Bommel sitting on the bench and maybe even causing turmoil in the dressing room.
He clashed with Demichelis at the start of his second season - the proud Argentinian could not stomach it to sit on the bench. That is why he left. He has his special idea about defenders - they have to be able to start the build up and he wants a right foot on the right and prefers a left foot on the left of the two central defenders. Lucio and his ways to play - especially his reluctancy to change his role - very early caused Lucio to leave for Milan.
He told Gomez and Tymo very early that they are not his buys and that he has problems to give them spots in his system because of the way they play. But - if you look at it now - we were a lot more successful with Olic or Mandzukic as a striker even if they are less potent goal scorers. And Tymo never got more than a bit part role with Heynckes, too - and they would not have any chances playing with Guardiola.
Ribery had his problems - he had no "fun". But the Ribery of 2009/10 was not disciplined - the Ribery of today is. I do not think that he is an example for anything. The Ribery of 2009/10 would have big problems with Guardiola, too...