These people are only human, and to hold them to a standard higher than we hold other people seems a bit unfair. Sometimes they say the wrong thing, that can be interpreted certain ways. It's not necessarily their full and whole intention or meaning, and it can be hard to communicate the right thing when everything you do become soundbites to be taken out of context.
I know for a fact that MP tries VERY hard to stay away from the drama. I've witnessed it myself in my own interactions with him. Obviously the split itself was hard (and no, the full story of what went on during the split isn't public knowledge), but part of the problem is people are still going on about it a decade later. And bringing it up at every corner. And sometimes words slip out, or you hear something wrong (which i think was the case here) and you respond in a way that may be interpreted in a way worse way than you actually intended.
If MP hated James that much, would he go on a tour that essentially just copied what James did a short year previous? Obviously there are some unresolved issues, and some friendly and not so friendly jabs, but I think the whole "hate" situation is way overblown. Obviously I can't go into detail as it would betray personal trust, but in my experience this is more like a falling out between friends, where there's still a fair share of mutual respect but also some unresolved resentment which colors the relationship still. But the main gist I've gotten from both camps is nothing but love and respect.