sorry I'm so late in seeing this!
I do understand about the 'getting used to it?' part? But I'm now on my Third Guard or whatever ya call it in the last 20+ years. And, I still feel the soreness from sleeping CHOMPINGNESS-es! BTW? I wore out the first two! I am definitely a chomper!
Just sort of incorporate the insert thingie into your nitetime routine. That is what I do and I am successful about 95% of the time.
Don't be hesitant tho, if something is rubbing or not right with the gard....I've always found adjustments are easily made.
As for other tenseness? Now that you are Aware of it? Check out 'body awareness techniques'.... Once you know, you can deflect/redirect the tenseness, if not avoid it. Just even being aware? You can tell yourself OH? OK! and that can do the trick at times...not always tho. Sure cheaper than lots of other options, and better than more medications?
Chomp safely now!
's - j