I have been struggling with this a few times as I can’t get my mind to print this shifting music thing…
For me, I’m sure that comes from my 20+ years of using FInale…
But I too would love to be able to set a signpost of some kind at the end of my section-in-progress that will block insert mode from pushing the following music around.
I turned to this method too when (once again) I got caught out by Insert mode. I suppose the idea came from my familiarity with Sibelius, where a doubled-duration group of notes gets put in a new score automatically, requiring the user to paste the result back.