$900 is two track day entry fees at MSR Cresson and you'd still have gas money left. The seat time teaches you how the car actually behaves when you ask it to do something, which is the part nobody can put on a graph. A dyno sheet is a receipt for a number, not a skill.

My wife used to give me crap about buying the rotisserie bird instead of roasting my own, then one week I timed it. Between the raw chicken, the seasonings, the gas for the oven, and the two hours of my Saturday I wasn't getting back, the math was not even close. Now we grab one almost every Sunday and I pull the meat for the week, sandwiches Monday and Tuesday, then I toss the rest in a pot with the bones and some celery tops for soup. That stock alone saves me a few bucks a week and tastes better than the boxed stuff anyway. Some shortcuts are just smart, no shame in it.