It was used for decades among gamers before the strip came out. Talk to anyone who gamed before then and they'll say as much. The problem is, gamers don't write all their shit down. Most of our memes were verbal and spread at cons back then. It's not the trope namer. It just used an old phrase. I've been at cons since the 80's which is when I first hear it. This is not a new phrase.

We had a whole thread about it which was unfortunately deleted in the great forum purge, but there are fan zines from back then that used the phrase as well. I just don't feel like digging through my mum's basement again and reading through a bunch of thirty year old magazines. Just because it isn't on the internet doesn't mean it doesn't exist.