To trade TP and still be a contender, they'd need to get a great haul. Something like an above average point guard along with two or three quality role players.
But with the Spurs trying to include RJ in a TP trade, there's no way they get anything close to that. By including RJ, the most you can hope to get back is probably two decent players and a draft pick.
In such a scenario, I agree with baseline bum. If you trade TP for peanuts, you might as well trade Ginobili now. And then you have to have serious talks with TD about what he wants to do.
Personally, I want the Spurs to give it one final shot. But if the front office wants to move toward rebuilding, I don't want it to be half-assed rebuilding. Either keep trucking or tear it down. Nothing else makes sense.