I'm guessing the tensions came from worrying about antenna crashes. I have to go through that all the time with my vision. Sometimes I get a bit skiddish when really close to the antenna, and tend to flat a bit on high notes.
I also clench my teeth a lot while playing, and noticed the tensions, but never paid atteinton to it, til finding your post. I tried relaxing my jaw, and sure enough the tensions were reduced.
thanks for posting this.