"I didn't say anything." Which is the supposed!adult's version of well he started it and seems to come out of Jane with the same level of maturity. It rings a little like misplaced passive aggression, and the extent of Jane's self-awareness in the moment does at least make her sigh.

"Rule number 3 of the lab: if you don't have a good reason not to do it..." Then it's an acceptable action. Yeah, that's the Foster way. And she did hire Darcy, so. Can Jane really complain?