I agree with this.
Also, it's worth noting how little Colby really did to save himself. Tom gets some credit for finding the Immunity Idol and making a deal with JT earlier on. Still, this week was almost completely due to JT, not Tom or Colby.
I do think it was a questionable play by JT, though, for a couple reasons. On a self-preservation level, he risks Amanda/James/Rupert/Candice turning on him immediately. Granted, it would take only grabbing one of them on his side to keep the numbers with Tom/Colby, but it's still a definite risk. Especially after blindsiding all four of them. Why put yourself in a minority alliance when you're already on top? If you want to keep Tom, try getting out Candice next week. Or just sacrifice him.
Second, there's the tribal side of it. We've seen time after time after time after time that a splintered tribe can get completely swallowed when a merge comes. Having all these two-people alliances hanging around is messy, and just gives the other tribe more room to take the upper hand.
Of course, the "splintered tribe" tends be a scarier problem when your tribe has more people at the merge (see Rotu, Timbira), which hasn't been the case for the Heroes thus far.
A 2003 IceCat original