About autopotting and different pets

However, auto-pot is known to fail when you are potting manually, buffing, or looting. It might be that Mechanics' skills/summons/mount/etc interfere with auto-pot relatively frequently.

This sounds about right. Mechs get a buttload of abilities to activate all the time, so it's quite easy to miss a pot. On my own Mech I use auto-pot more as a contingency button rather than relying on it.