No! A TRV just controls the flow of water through the radiator, so it does not matter which end it goes - it's the same water coming out as goes in.sounds like a god idea - but, wont that just mean they control the flow of water BEYOND the rad?
See How the TRV works (Courtesy of Danfoss)I dunno how these things are supposed to work
The animation is not strictly correct as it shows the TRV acting like a switch - open or closed. It the system is correctly set up it will act more like the accelerator on a car, keeping the valve open just enough to maintain the correct flow and modulating slightly either side of that position as required. If the rad temperature is fluctuating between hot and cold, it's a sign that the system is not correctly balanced.