Damn, that looked fun! And if you don't have an occasional off-track excursion, then you're not really pushing hard, LOL.
That didn't look like a typical HDPE event, was that some sort of race? I've gotten to the point that I can drive pretty quickly by myself with a wide open track, but I tend to get very cautious when it comes to passing. I typically pass on the straights, but I see you passing pretty much any where, LOL. That's a goal of mine, to figure out how to safely pass in more places on the track. I've had a few close calls with cars even in the advanced groups where they will unpredictably go offline towards me mid-pass.
I will be tracking Buttonwillow on Dec 21 - 22 in the Camaro, care to join me?