Lews Therin tells us a few things about Demandred...

"I thought it would be in the south where they struck... I'm half-certain Demandred is involved. He has never been comfortable without an army. But Caemlyn.... yes, it's a clever strike. I told you they would try to distract us."

"Its exactly the sort of thing he'd try. Separate your foes, then crush them one at a time."

"It was one of the oldest strategies in warfare. Demandred himself had discovered it in the old writings. They'd known nothing of war when the Bore had first opened."

"Of all those to turn to the Shadow, Demandred's betrayal seemed the most tragic. The man could have been a hero. Should have been a hero. I'm to blame for that, too, Rand thought. If I'd offered a hand instead of a smirk, if I'd congratulated instead of competed. If I'd been the man I am now..."

It's interesting to see how much Demandred has the ability to vex Lews Therin and how he's going to come to the forefront as a Forsaken in this book. They are similar in many ways. I wonder if Rand will end up apologizing to Demandred for treating him unfairly at some stage? That is certainly a possibility, especially with the new Rand. Either way, it's going to be interesting to see how Mat challenges Demandred's tactical abilities.