I am in the process of redoing my shower stall and am removing the old separate valves with a single valve mixer. The house was built in 1977 and they used what looks like little desurgers on each leg of the piping. Is it necessary to maintain the desurgers or can I just cut them out too?
Those are most likely "integral-stops" which are designed for shutting off the water to the valve without shutting all the water to the house off..I would remove those as they can inhibit the volume passing to the new valve/valves. erik