Post making contest 6.0

Rule 4 doesn't seem to be caused by time of day (two identical posts in the same minute don't proc it, IIRC) and there's no feasible way their post numbers are related. The only other context-related thing I can think of that would make identical posts succeed at different points is how they link up to posts above/below them, but identical sequences of posts also will randomly not pass rule 4.

I'm very confused.