Alternator charges ONLY when EOC?
 

I thought the best time to have an alternator put drag on the engine is when one's foot is off the gas pedal.

Think of it as regenerative battery charging using the alternator instead of the brakes.

Has anyone seen / done this?

Thanks,
Doug in Oakland, CA

Yes. You can do something like this with either "EOC" (engine off coasting) or "DFCO" (deceleration fuel cut off). I have done both quite a lot, but I am much more comfortable with the latter. My alt is wired through an on/off switch. When I am in a long braking situation of some sort, I turn on the alt and engine break in gear. My volt meter usually shows 13.xx or even 14.xx. I can do the same thing during EOC and even extend the coast by fully opening the throttle, but it does not feel worth it for all the added hassle and the feeling of pushing the engine into weird territory. Haha!