Is this possible?

I am following the idea in this thread here: thermostat with dimmer

In that thread, the rheostat is meant to control the maximum temperature in case the thermostat fails in the on position.

Say I need to control two UTHs at two different temps. I'm assuming the warm and cool sides changed temp equally. So instead of using two tstats, what if I used one? The probe would be placed on the warm side, controlling the warm temp to about 93. The cool side UTH would also be plugged into the tstat, however, a dimmer in between the UTH and the stat would regulate the max temp. If I dialed the dimmer down on the cool side UTH, would I be able to achieve a temp gradient?

My understanding is that you can do that with an on/off t-stat. A proportional t-stat is basically a dimmer that controls itself, and there is some reason why you can't use 2 dimmers in line with each other.