Hi Josh,
I don’t know the answer myself, about why Al is the only person from Sierra I still hang out with. Roberta and I travel nonstop so we are rarely in the same city as the various Sierra people. Even as much as we enjoy hanging out with Al and his better half (Margaret) we only see them a few times a year.
As to AGI (the language we used for our games… I was heavily involved, but don’t remember writing much of the code, if any. I don’t remember who wrote it. I think it may have been an engineer named Bob Heitman? I don’t think Jeff Stephenson, who was the father of SCI, was working at Sierra yet. There was another engineer named Chris Iden. Maybe him? Or, maybe it was me? It’s strange I don’t remember, but .. it was 40 years ago.