I agree with you that LTT wouldn't have complete knowledge of what was developed after he went mad. But I doubt something was done. There are two facts that we know of:
1) the Opening of the Bore destoyed the only likely place that had any potential ability to Heal the taint madness. Granted, there are could be other places where the Great Healers of AoL would have survived, but I doubt it. And besides, I would think that they have their hands full with other stuff that was happening.
2) from Rand's visit through glass columns, we saw how mad channeler destroys all his Aiel. It took a long time and there was never mentioning of some kind of "Healing" that would have been done to stop him. Only helpless Aiel Singing to calm him down. That should inform us that there were none at this time.

As to what Ishamael said to LTT, I agree with FT. Most likely he ment that there is a weave that grants few minutes of sanity and that's precisely what he did.