Got a reference!
Iyokus speaking to Eleazaras
"aside from what you and I witnessed ten years ago, we know next to nothing about their Concerts."
pp. 174-5 Warrior Prophet, US edition, a few pages into chapter 8
So the Scarlet Spires *think* the Cishaurim use concerts, interesting...
I would like to take this opportunity to plug the crackpot that the Cishaurim are behind so much of the unlikely events in the stories--they are right there and could be subtly manipulating events in the Inrithis favor quite easily!