Never owned a hybrid before, but I feel like taking a car into a dealership and saying "Light comes on once every 4 months. Don't turn car off or it wont appear for another 4" is a fools errand.
To answer your question, the only symptom is the light. I've goosed it, and received full boost/assist with the light on. I've cruised up the speed and downshifted my way to full regen as well. There are no symptoms other than the sheer terror of the infamous orange light failing to disappear on startup.
Are you suggesting I take it in anyways? I see how my stance would be seen as downright irresponsible. I realize this now, because this morning the light popped on again. 2 days straight is strange, and it always seems to pop after the car has sat overnight.
Allow me to ask for help, then:
How do I present this issue to a Honda Tech when I take it in? Do I request they do a diagnostic of the battery? or a tune-up? Or do I make it clear that there is an electrical gremlin I want them to chase for $110 an hour?