His manners on the pitch were the same for PSV, he rarely had to track back after losing the ball and he didn't smile alot. He did defensive duties in the big games but he was the main man offensively so he was relieved of tracking back usually as he'd offer more going forward on the break. He will need to improve on this obviously, for now it really is one of his weak points.
I can understand that for people who didn't know much about him before he transferred to Manchester United it's easy to buy into the rumour mill, but I am still convinced his attitude is one of his (if not, the) strong point. I just think he's an easy target to be lauded as having a bad attitude (since he used to have one and also looks like it), the same happened in Holland yet he rarely made the news for doing stupid things. Especially since he made the first team of PSV he progressed on and off the pitch like you expect from a top talent.
I do think that he's a type that needs a boot up the arse every once in a while, but Memphis is very grounded in the fact that he knows he hasn't made it yet. I doubt he's sulking for being benched, I'm sure he knows fully well he hasn't been good enough. He has confidence in himself and he's one of the players that always gives it all in training, I don't think I've ever heard of him slacking during training. He really lives by the motto he has tattoo'd on his chest: Dream Chaser, I doubt his dreams end with a spot in the Manchester United reserves. Memphis has a plan in his head for how he wants his carreer to turn out and so far he's taken every step with relative ease untill his transfer, now he's hit his first big hurdle which he struggled with in his carreer. I doubt he'll give up though, I cannot wait for him to adapt to the PL and show that he's already a better player than he's shown so far.