For the last 15 years I have always groaned when having to remove a bit from my P-C 690 router. I always put one wrench in my left hand on the bottom nut and the other wrench in my right hand on the collet nut. To tighten was easy - simply squeeze the two wrenches together as if they were pliers. Worked very well, but loosening was always a challenge because I had to pull the two wrenches in opposite directions which exercised muscles I used infrequently and really did not care to bulk up on.
Lo and behold this weekend I made an amazing discovery. Simply reverse the wrenches making the top wrench in my left hand and the bottom wrench in my right and squeeze just as if I was tightening and the collet would open like a dream. Where have I been and why was this not so obvious to me?? Talk about a lack of brain power ...