SEASON FINALE: I don’t recommend watching this show, really, not any more. But I do marvel at both its impact and its longevity. With tonight’s episode, Grey’s Anatomy concludes Season 13, a truly impressive stretch. And it’s not just limping to the seasonal finish line – it’s sprinting there as ABC’s most popular drama series. That’s why so many of ABC’s dramas, for good or for ill, tend to be painted with the same Shonda Rhimes brush, whether they’re shows from that prolific producer or just shows striving to copy her feverish, popular program elements.