I think pipe design makes a difference here as well, with respect to salivation. A larger, bent pipe may be more conducive to collecting saliva in the stem than a smaller billiard design, for example. Something to consider. Also the way the pipe is held. If clenching just behind the button and allowing the pipe to have a downward cant, also more conducive. If a smaller, lightweight, straight billiard is clenched a little farther back with the sides of the teeth finding a comfortable spot which reduces weight on the teeth and keeps the pipe more upright, i'd think this would both be a more comfortable position for longer clenching and less conducive to the collection of saliva in the process due to position and orientation.
In addition, over life things change as well. I never was much of a clencher for most of my piping years until relatively recently. My tastes trended toward larger, chunkier danish styles and slowly gravitated toward lighter, Italian briars and finally i'm starting to really appreciate smaller bowls and clenching became a natural part of that experience. Also find myself smoking more pipes while driving these days, which used to be a time when i'd smoke more cigars. Things change, preferences evolve, techniques develop, the discoveries never end, hence we call it the pipe journey.