I didn't see that at all. I thought, with the exception of the question about his lab in a barn, that he was not snarky at all. Especially when compared with others!
But I swear, I am riveted! This guy has reinforced the case's state so many times! The smell so foul he had to do something to prevent his lab from being stunk up, Dr. Vass being a qualified chemist even if it is not his title, the high levels of a volatile chemical, etc., etc. He is making JB look like a clown. I am stunned that this is a defense witness. Stunned.