I would have to say taking it apart especially if it is all 1 color the knots look different when you have to untie them and if you burned a few together its nearly impossible unless you spike the knot to pull a single line and burn the endings apart using the pull strain to open it up.
I have several small "spikes" from different objects to pick apart the knot which help,.. old knitting needles, piece of brake line, an actual mini marline spike , I have even used finishing nails to get a loop started..even then the wrong
line gets in the way and lets you know after the cut
Usually my
become "test pieces" I just untie what I can and use the loose ends to try a new knot or combo I'm dreaming up and the untied part reminds me that it either looks all right or entirely wrong and saves time and effort in the long run since it was waste footage anyways,a plus is that I don't burn spool line trying the next new thing..
John
And yeah its frustrating when you try tying a knot you have tied before and spend a week relearning it