A couple more points about the way I’m setting up the tempo change clips:
Qantization is set to None. No need to wait until the beginning of the next bar to get the tempo change going.
For Launch mode, I’m using toggle.
When combined with no quantization, toggle mode makes it easy to jump to a new tempo by a quick “double-click” on the clip to start the tempo change, then immediately stop it.
…so in the above example, it’s easy to jump directly to 80, 82 or 84bpm.