I've added Sta-bil to EVERY tank of fuel in all my small engines for the last 20 years. They all continue to start easily and run reliably, from my 20 year old lawn mower that hibernates for 5 months at a time to my chainsaw that goes years without use. My 9 year Yamaha generator still runs like a top. I don't bother draining fuel, or sticking with ethanol free blends, or even running them monthly, but I do only use 91+ octane (for other reasons).
I have troubles understanding why some have so many problems with gumming up. Maybe different fuel blends for different geographic regions?