I use dimmers exclusively with no temp adjustments being made. I still check the temps twice a day, but thats because I'm obsessive-compulsive about it, lol, and its not hard to take 2 seconds and walk by to check. But that is also because I use them properly. I have a house thermostat that will cut the heat and air on without having to switch from heat to a/c. Also, I keep the snakes away from any outside doors or possible places that could draw a draft when opened. Keep them away from any air ducts, windows, or really high traffic areas that could cause too much air movement. It sounds like alot but it's really not. Or go the easy route and invest into a thermostat. I initially went with a dimmer just to fix the issue with the intentions of getting a thermostat at a later date. But I have had no issues and I love it.

One more VERY important thing. If you do go with a dimmer, mount it in a box with a lid or find another way of making it so it cant get bumped or turned up/down by someone who doesnt know what its for. I have a 3 and 4 year old that will push or turn anything if its in reach, and even if its not, they still find a way of touching it. I have a nice case I made for mine with a locking glass front so no one but me can get in there and mess with it.