Would love for the Jays to get used to giving long relievers 4 inning starts every so often. It's really no different than what they are doing but they will know that it's their game. I really don't see this being Biagini converting to a starter. It's just him doing his relief role at the start of the game.
I think he can be effective once, maybe twice through at best. This is true of many pitchers but when one is really effective in this role, and there is no wiggle room for testing...stick with what you know. If the Jays fall out of it...test away.