I think he has started slowly tone down like cms said he only goes up there for his 2 main moves whisper/swanton. And he will prob take the odd sick bump in big ppv matches Mania/summer slam etc if the need be. But he is getting older and his body must be messed up with the mad shit he has pulled off in the ring since he started. Plus if he wants to b a main eventer it wouldn't damage his chances being less of a spot monkey and do more in ring stuff instead of on top of the ring stuff if ya get my drift
As for reforming as Tag team with Matt to share the work load of big bumps Jeff took most of the big bumps a lot more often than Matt did. Matt was more of a smash and bash and technical inside the ring with the odd big bump. But Jeff has always been the one flying and taking sick bumps so that really wouldn't help Jeff out bump wise or his quest for singles main event spot.