as I understand the process the lacto will either work very slowly or not at all at temps the ale yeast will like and the ale yeast will just throw a big hot mess at the temps the lacto like. mtnrockhopper's idea sounds like a winner to me. I'm planning my first BW this summer when temps at my house reach ~37-45C, 100-113f, or 310-318K whichever comes first.