But it is important to run the engines up to normal temp about once a month. This keeps everything internal coated with oil, preventing corrosion. I too always topped off and treated my fuel tank each November with Sta-Bil. If I used the boat after that, I would top off the tanks again, but never added more Sta-Bil.
Every winter I would go to my boat at least once a month to run the engines, raise the OD all the way up and all the way down a couple of times, and did a visual inspection of all the gauges, lines, etc, looking for anything which didn't look right. I usually did my annual maintenance and bottom painting in January when the shops need the business and often offer a discount. Wait a couple of months, and then you have to get in line!!!! This is a good time to have your batteries checked and, if needed, replace them.
This worked for me for 19 yrs and I had minimal problems with my boat. I preferred an ounce of prevention and not having my on the hard during the boating season!