JRBarrett -
The "automatic" mode is used to prevent electrically-heated sensors (pitot probes, AOA vanes, TAT probes etc.) from being switched "on" when the aircraft is on the ground.
There we go again....."automatic". I never flew an airplane that had that. We had a Checklist that had Pitot Heat on it. Simple. In other words, no problem having it on while on the ground. And the 'automatic' portion (which there was none) couldn't fail.