Missed that event but wished I could have made it... I really like Buttonwillow.
One observation I can offer is that you seem to get on the gas at corner exit without unwinding the steering wheel in several of the corners on the video. I understand that this is a compilation of the fails so not sure how the good one looks but wanted to point that out. If you pay attention to unwinding as you press on the gas pedal, your chance of coming out of the corner without oversteer will increase drastically
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