That cheap laser probably had a bubble vial that was barely accurate to begin with. Once you use a rotary that self-levels, there's no going back to guessing if your lines are straight.

Yeah, expired baking soda doesn't usually foam like that, it's the fresh stuff that goes wild - you probably just used a new box and didn't realize it was still active.

That bearing roller tracks true for me too, no more fighting the seam.

Holy crap, I-75 through Atlanta during rush hour? That's like driving through a live video game on hard mode. I've lived here my whole life and I still take side streets just to avoid that stretch. You went from zero to nuclear chaos for a dentist appointment. That's either incredibly brave or slightly insane and I mean that as a compliment.

That 5% starting point is smart because it keeps you in a safer window. The vacuum gauge is the real indicator there, not a hard rule. If you see it dropping fast, you know the material is too thick and you need to bump the throttle back up before you lose suction entirely. I'd add that keeping an eye on your discharge pressure at the same time helps too, because a sudden spike there means a plug is forming before you even hear it cavitate.