Working on the "Countdown ii V" with a few students counts as practice for me! I tell students all the time to practice "fast in slow motion." The tendency is to play faster than eighth notes when it's slow. At 200 bpm plus, you will not survive if you practice this way.

After working this progression in 12 keys from memory starting around 80 or slower, I've gotten up to here which is 160 over some tunes. This is still fast for me and will take alot of time. Notice how uneven things are, and how when I lose this new concept, I revert back to old things I know. Still though this is a lot of fun. I feel like I'm tracing Coltrane's footsteps.