Good beginner's lesson -- thank you. I have two comments:
I typically have better luck ramping up slowly to a bubble squeeze (the traditional 50/hr after an initial soak temp to the bubble squeeze, so for me -- sys96 -- hold at 1100 and then ramp at 50/hr to 1250 and hold the allotted time).
Interesting that you left off using shims/chads.
Keep the great info coming