For those of you who have ever wanted to know how not to brush off an entirely too-harsh thing with "humor," here's how not to do it:
Do not say, after saying
this and getting back a panicked and penitent response, "Couldn't let you off the hook without even a little preaching, could I?
That date will not cause me any serious extra work. Better that you took the course than
not. So don't loss any sleep."
Sigh. If I hadn't said I would talk to him at class, I'd totally skip it tonight...