As someone who has burned 24/7-365 for over 40 years, I am convinced that no damage or degradation to the boiler and appurtenances occurs when you keep the system active. Sure I understand the need for an off season repair or cleaning, but think of an fine automobile, bike, boat, truck, etc. that is left out of service for 6 months and then returned to service.......
My .02 says it is much wiser to keep things in concert with your lifestyle, and if you want to shut it down, fine, BUT you better do some housecleaning and rust prevention work in the interim.
I've seen AA boilers come to me that had to be sandblasted internally to remove impacted ash products.......Zero maintenance is not a money saver! Like the Fram man said: Pay me now...or pay me later.
I've seen EFM's so plugged up that the auger wore through at the pot.....grates with baseball sized holes...still burning. Many of you saw the EFM Matt DeRenzo was called to repair.....one of the worst I've seen...and son of a gun if he didn't return it to service. ( I'm betting he lost some skin on that job, and emitted a couple colorful words too!)
Yes, I have a sizable dump zone in the form of a radiant slab area, but overheating is never an issue with or without one.