Mike Birbiglia is known for mixing up the standup formula. Instead of doing multiple bits, he often prefers to tell a few long stories intermingled with jokes in order to get the emotional point of the story across. He is quite good at it: His last special, “My Girlfriend’s Boyfriend” delivered personal stories of Birbiglia’s with raw emotion and humor, without being excessively self-deprecating. His autobiographical film Sleepwalk With Me (currently on Netflix) poignantly captures the isolation and sadness of being a traveling comedian. So, I was disappointed this past Wednesday at Statler Auditorium when Birbiglia performed his new show, “Thank God for Jokes,” ditching his winning formula.