Another issue I have with Davey adhering to the roles of the pitching staff. Aside from shutting down Jackson an inning too early, I believe, he also mentioned that Gorzelanny had troubles getting out left handers. Considering he's a left handed pitcher, that was a problem but he's also a long man. Being the long man means he's supposed to pitch multiple innings which means he's also going to face a number of right handed batters as well. In last night's game, in the 6th for the Astros, the upcoming batters were L-R-L-S then the pitcher. I think this played a role in going to Gorzelanny at that point.
The number of left handed batters immediately coming to bat shouldn't be a high consideration for using Gorzelanny. If he was specifically concerned about getting out lefties then he should have used Burnett in the 6th, assuming he takes Jackson out (which I still disagree with) and then gone to Gorzelanny in the 7th. Again Gorzelanny is a long man so he has to be able to get both lefties and righties out.