I could never find an answer to who was on the obsolete entity guy, and after encountering him again when making my library notes I decided to go straight to the source! (lolol pun) His reply. (just shy of three hours later, so fast!) He CC'd it to the two mentioned, and a mere 21 minutes longer: Valve is so great about answering fan questions. I knew there had to be some fun stuff lurking here.