[Mr V]

You really should start the vehicle with the 12v starter at least once per year. If you take it to a reputable Honda dealer, that pays their technician the proper rate for an oil change service for an Insight, and the technician doesn't "forget" to do it so they can bill more hours, they will "exercise" the 12v starter at least every other oil change if not every oil change. In other words the 12v starter is never properly exercised unless the owner does it on their own or the vehicle is operated in conditions where it won't use the IMA to start the engine.

This can be done one of two ways. You can either turn off the IMA battery pack with the switch under a cover under the mat in the cargo area (Honda recommended method) or you can remove the #2 fuse.