Indecisive ECU?

On rare occasions (maybe once every week or two) when I stop at a light and the ICE had been running it will shut down briefly (or seems to), then starts back up, and cycles like this up to about 10-12 times usually ultimately shutting down unless the light changes and I take off before it does so. Usually occurs with AC on.

I have just wondered if there's a stage of battery charge v.s. Energy demand when stopped that creates this seeming indecision on the part of the ECU on whether to shut down. That is:
Condition 1)Car stopped, Engine warm, battery charge adequate (just barely)--decisions is to shut down

Condition 2)Immediately post shut down the AC and other accessories drain the NiMH just enough to meet the threshold for ICE to recharge despite being stopped--decison is to restart

Condition 3)ICE almost immediately pushes battery charge state over the threshold and decides once again to shut down.

Or is this just a quirk. Note that this is not the same as the shudder when the ICE is shutting down. I still get that a little bit, but not much or often.

 

I pretty much leave it on auto or turned off completely, so the computer is deciding my AC setting.