TS2 - Handle is Difficult to Remove
TS2 - handle is difficult to remove
Most likely, the edges of the flat on the stem where the set screw presses have been distorted and have developed raised areas over time as a result of the screw pressing on them.
To remove the handle: rotate it back and forth clockwise and counter-clockwise on the stem (actually twist it on the stem, NOT move it around as you normally do to adjust the water flow/temp) while at the same time, pulling it up and off the stem.
Before reinstalling the handle, remove the distorted areas on the edge(s) of the flat by filing, sanding or grinding.