XT has reached is goal imo to put more pressure. It has also brought out the worst in some people and pointed to some related problems (centralization of control over the places the community uses to communicate, for example).
I ran XT on my node for a while for exactly this reason. I never intended to blindly follow Hearns changes in the future and I think I'm not alone.
The biggest mystery to me is how we arrived at this situation, where Gavin and Mike (felt they) had to resort to the fork
Sure, a certain number of maxblockheads resisting any and all changes to the protocol I can see as being unavoidable. But why Gavin didn't manage to convince a majority of the core devs to support some adjustment is still not entirely clear to me.
Either Gavin tried to push exclusively his idea of an adjustment (which, admittedly, can seem a bit drastic) - in that case, it's a failure on his side to compromise. Alternatively, there was a consensus by the rest of the team that the current limit better not be touched at all right now (in which case, Gavin did the right thing, even if the right thing is a huge mess as well).
From the outside, I got the impression it was a combination of the two above, but I wonder if someone closer to the core team knows if one of these two aspects was the dominant factor.