What a great story, Keith. I've been interacting with you for almost 20 years now, and I've learned so much from you, and from Denny, and so many others, on this forum but a great many forums outside this one as well (remember MoreBeer?). Great to see that you still haven't lost your passion.
Personally I don't brew so often anymore (still have 7 cases of bottled beer, mead, and cider in my basement, most of it commercial! -- used to have 11+ cases so I'm working on my "drinking problem"), but it is in fact my love for all the math and science that draw me back to this hobby, time and time again, back to the forums and to spreadsheets if not to the actual brewing, more than anything else.