If you don't need to impress anyone, why cut it at all?
One morning I decided to blow-dry my hair. The dryer had a hard time starting. Then a chunk, chunk noise occurred. Finally, a stream of brown paste shot out from the dryer. I threw it away and never used one again.
My coarse, gray hair was always wet morning, noon, and night. It was awful. That is the reason I get haircuts even if I'm not trying to impress anyone.
The technique is mostly to avoid damage and to avoid frizz, but it is also surprisingly faster than the "shake" method. Maybe with a microfiber towel like you said it's even better.
Why not even shorter? This time of year cold is a factor, otherwise mainly habit. And fully short (almost or entirely not there) involves blades, I'm not trusting myself not to cut the back of my head to shreds (again, I'm often not physically well coordinated!).