That’s funny, I’m not even sure what the D is supposed to expand to, in that insult. What a silly and lame thing to use as an insult.
I’ve been using it because having some random letter capitalized seems to be the totally unsurprising for this sort of plumbing software. (And by plumbing, I mean: very useful and helpful boring stuff that deals with messy problems that I’m happy not to care about, just to be clear that I mean it positively, haha).