That is very very true.
Case in point;

95% done
98% done.
Those were 8.5/10 difficulty.
Dropping three floor means the door jamb no longer reached three ground making it at least 3x the difficulty.
I managed to figure out a way to mate with the jamb by cutting more off the bottom so I could go straight under the stop, problem being then that the jamb was twisted like 5°