So, Robin wants Barney to get her dad's permission to marry her, Ted (surprise surprise) still has feelings for Robin, and Marvin is constipated and cranky. This episode wasn't terrible, but it definitely wasn't great. Ted once again flip flops on his feelings for Robin, which at this point has most HIMYN fans repressing an urge to throw something at the screen. The highlight of the show was easily Ted and Lily's rooftop confessions, and Neil Patrick Harris manages to deliver the one good joke in this episode. Despite the story revolving around Robin and Barney, Robin has very few lines. That may have been because Cobie Smulders appeared to be battling a cold. Interestingly, although the bulk of the episode centered around Robin's father, very few reviewers have mentioned it much.
The scenes with Robin's dad were confusing at best. The writers couldn't seem to decide on what personality they wanted to give the dad. He has apparently accepted that Robin is a girl, and even embraces it, without explanation. He claims to be "fun" but is still just as tough as before, and about halfway through the episode the writers start turning him into a manlier version of Lily's dad. Meaning, he is so wrapped up in enjoying his own life he doesn't notice how unhappy his daughter is.
Finally, we learn something big about the mother. The new information is in fact so big that it calls into question just how much is left to reveal in the series finale. However, with eight seasons come and gone I'm sure the writers will be pulling all the stops for when Ted finally finds "the one".