As an horrified LTT revealed to Rand in TGS (and Brandon confirmed it was right in Q&A), the True Power is Shai'tan.

I think it's totally impossible to harm Shai'tan with the TP (destroy what Shai'tan has done possibly, at least for as long as he doesn't realize it and cut the channeller off the TP, but harming the TP would be like destroying the OP... it doesn't sound possible, short of such a huge amount of balefire it would destroy Creation). It's even possible the TP weaves do what they are meant to do because Shai'tan let them, but we don't know if the TP passing through a human still as a will of its own, or if Shai'tan must submit itself to control by someone else (that might explain in part why he so restricts the use of the TP to people totally dedicated to serving him). It's not far fetched to think Shai'tan has control over what's done with the TP - that he can alter what someone has woven with it though, (ie: the TP is "alive" and has a will, Shai'tan's will) and maybe why Rand and Moridin got linked when they made the TP and OP touch at SL (ie: Shai'tan seized this opportunity to link them, a bit like he seized the opportunity of the TP and OP touching during the strike to taint saidin).

Anyway... I agree with others. Rand may use the TP is some way at SG (for instance, he could bait Shai'tan to attack and use the evil of SL - Fain and his dagger - to cause both to destroy one another as he did at the Cleansin, but thematically I think it's pretty safe to say that when Rand touched the TP he hit an all time low. After that, he became addict to power and to destruction, and it seems it's access to an insane quantity of saidin with the CK which kept him from the temptation of tapping the TP again, until he put an end to his nihilism and darkness on DM, and turned his hitting the bottom of the barrel into something positive, a warning about his darkness/lack of feelings and humanity he won't give in to ever again, thus making him mentally stronger than he ever was.