It's totally not strict at any level. It's mainly about the director/editor relationship and the ability of the Director to actually cut.
I have one mid-range TV director who cuts selects for me for things like motox racing, partly to save money and partly because it HATE doing it, because the stupid numbers on the bikes are so small and often covered in mud. I get terrible squint headaches doing that junk.
Then, I have other Producers and Directors who have no knowledge and absolutely no interest in cutting. If they touched the keyboard in all likelihood it would just cost them more to have the cut repaired.
Then you have guys like the Cohen Brothers, who do it themselves.