Coalescent

Again, that's not my point. My point is Mark Twain's point: "The personages of a tale shall confine themselves to possibilities and let miracles alone; or, if they venture a miracle, the author must so plausibly set it forth as to make it look possible and reasonable." That's why Who has the arbitrary rule about not being able to enter peoples' timestreams more than once -- it's not because it's somehow a bridge too far in plausibility terms, it's that it's essential to preserve the ability to tell a coherent story. In "The Runaway Bride", RTD didn't follow that guide -- he just kept on introducing more miracles to deal with the consequences of his earlier miracles. Which makes it very hard to care about anything that's happening.