Fire Mage Rotation

Is it possible to sim casting combustion at 90%?

If you used firestarter to get crits until 90%, then used combustion to continue getting crits… that would be a longer period to be getting straight crits. I know everyone is using searing touch for the 30% mark at the moment. But if we could some how sim casting combustion at 89%-90% and then again on time warp phase… that might make a difference?

does anyone know how to do this?

nevermind it already does