If "fluctuations" means wandering up and down around the desired temp, I totally don't care.
A few years back I put a Taylor probe in my house electric oven and set the temp to 250.
The temp would go up to 275-280 and them drop to 220-225. It took about 7 minutes to drop and about 2 minutes to re-heat.
Quit worrying about my smoker after that
If "fluctuations" means drifting off the desired temp and staying there, I "fix" that and put it back where it belongs.
It's all Good.
"Flirtin' with Disaster" BBQ Team (RETIRED)
FBA and KCBS Cook and Judge.
Former owner of a WSM, a Smokey Joe, a Charbroil Commercial gasser (junk), the legendary "StudeDera", a Fast Eddy PG500, and Sherman.
Now cooking with a Yoder YS640
Proud Pellet guy cooking on real wood.