You probably have heard them as well. They include: The hero/heroine meeting in a certain amount of time. Only one point of view (POV) per scene. No prologue or epilogue. No sports heros. Never use was. And some contest judges feel compelled to use these rules when judging contests.
All books are not round pegs, but some seem to want to force all into a round hole. Editors want good books. Period!
Now, I'm not advocating not thinking about your manuscript. Certain things may keep the editor from getting to your wonderful prose. Things like a lot of typos or a hard to read manuscript. Or a failure to interest her/him at the outset of your manuscript.
So, what "rules" do you trample underfoot in your writing?