How would I know if I'm overcooking the CCA?
or even what that means.
My AGM Deep cycle batteries do have a CCA rating from the manufacturers data even though it isn't shown on the battery label.
The system off cranking for 10 or 15 seconds and then letting it sit for 20 seconds and then repeating it a couple of times can get you started in cold weather when continuous cranking doesn't work.
Supposedly works because compressing the air heats it up and this soaks into the cylinder walls thus slightly warming the combustion chamber to the point where the fuel will ignite. Possible works even better with the fuel shutoff held in so that there is no cooling effect from the fuel vapourising. It also gives the cold batteries a chance to recover slightly in between rather than rapidly dying from long continuous operation. Perhaps the plates also heat up a fraction as well and that makes a slight difference when every little bit extra helps
Also works on my Onan diesel generator that has faulty preheat system