I'm missing something? Brains?
There are worse body parts to be missing.

You're correct.
For one PWM signal, all you need is 2 interrupts. One to turn it ON, and a second to turn it off.

It's when you have multiple PWM signals that you need to be able to turn any one of the channels OFF, at any one of the 255 time periods. So you need all thoses interrupts for every cycle. Even though nothing happens on 99% of them.

But again, blinky BAM only needs 8, and MIBAM uses 16 (doubled for the mirror image).
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