And please don't be offended by my point, which was that I thought it was inappropriate for my ex with a PhD in physics to want SKnot's friends and their parents to say "Dr. Booger" when everyone else is going by first names.

"Hi, I'm Sarah, I'm Jessie's mom."
"Hello. I'm Dr. Booger."

(sounds more like a conversation at a medical/vet/professor office than at a preschool picnic)