Sooo... I potentially figured out why I have problems playing scales. You know how I've been doing strength training and noticed my pinkies are flying everywhere? Well, when I play scales and cross the 4th finger (of both hands!) under, my pinkies hook under my 4th fingers and actually push them off the strings. Nice. This has been going on for years, I bet. Yet another bad habit to break. I hope using my pinkies correctly actually helps my scales, and isn't just for decoration.

On the plus side, I played for 45 minutes without any flare-ups.

But, still...