No, infact I did not use an engine, but thanks for the compliment! The reason I was so sure was because - let's just say that on move 30 I had 2 seconds left on my clock (thank god for the 10 second increment!).
When I said forced, I meant without loss of material. I actually think that, continuing with the games moves, he could have played 15... 0-0-0 instead of 15... Rc8. This, I think, makes the sac unsound, but white would still gain an advantage after Nh2, f4, and h5, while black is trying for a minority attack on the queenside. Still, the position would remain unclear.
By the way, I haven't checked anything with an engine. I think it is more instructive to analyse it completely with humans first.
Thanks for the encouragement! I'm really disappointed, though. My preformance in OTB tournaments has been creeping towards 2000, and that second brain would really have come in handy.
Incidently, I did see ST's game beforehand, but it didn't even cross my mind!