would you use a rheostat/dimmer for flexwatt?

[The Serpent Merchant]

I use dimmers as a back up to my t-stat. If the t-stat fails on or a probe gets pushed off then the flex watt still can only get so hot. As long as you test the setting before adding the animal and the room is a constant temp you can do it. Should you? Probably not the best idea but it can be done. As for not trusting them Idk why. Most are rated for a min of 300 watts. Even using 11 inch fw you would have to run 15 feet of it to worry about maxing it out. The summers I use are rated for 600 watts but I use one for every 10 tubs in conjunction with a t-stat.

I'm not worried about maxing out the dimmer... I'm worried about the flexwatt getting way too hot. The problem is that resistive heating elements just keep on getting hotter and hotter even when the amount of power being applied is reduced (lamp dimmer) As a short term solution (a few weeks) it should be ok, but I cannot in good conscience recommend it as a long term replacement for a thermostat.