You obviously are a bit mistaken on the facts, which isnt surprising since generally you sort of talk without any actual knowledge of the situation. Pro was my _original_ 39 guild. "Jumping on the Pro bandwagon" doesnt really apply when youre one of the founders of the guild. I went to Team Play because when I played 29s they were the most fun I had had playing the game, and I had alot of friends in the guild. Unfortunately a few of them had too many commitments outside of WoW to get back into competitive twinking again.
I only left Pro (of my own volition) when it was made clear to me that they were mainly coming to Nightfall to do arena, not premade. After talking with a few people recently in the guild, they stated that they were getting more and more interested in doing premades again. So, since TP wasnt active enough, and Pro was picking back up where we left off, it was a natural fit.