At work I was given a generated password (not my login password for context) of random words with numbers replacing/inserted at random points which I quickly memorized and used several times a day.
After touch typing it through muscle memory for 6 or so months one day I misentered it a few times in a row, and I realized I had no idea what I actually had been typing the whole time (I knew the dictionary words, but the combination of numbers and where they appeared was the issue). Spent a while trying to zone out and let the muscle memory take over again but didn't work and finally gave up and asked for it to be reset.
After touch typing it through muscle memory for 6 or so months one day I misentered it a few times in a row, and I realized I had no idea what I actually had been typing the whole time (I knew the dictionary words, but the combination of numbers and where they appeared was the issue). Spent a while trying to zone out and let the muscle memory take over again but didn't work and finally gave up and asked for it to be reset.
Very strange experience....