7.4/10. This one loses points for being mired in the Ted-Robin-Barney love triangle, but gains some back for making lemons out of lemonade with it to some degree. I'll be honest, I pretty much despise the big exchanges between Ted and Robin in the bride's room here (despite Cobie Smulders giving another very good dramatic performance), and it's only hurt by Barney being pretty dickish to Marshall and Lily by crapping on their vows and their "double flush" of a wedding. The latter just feels like a bad attempt at comic relief that leads Barney into some unfortunate unlikable territory. The former is more overwrought melodrama with a theme of "love doesn't have to make sense" that once again, feels like a weak attempts from the show's writers to spackle over how little any of the romantic elements with Robin, Barney, and Ted over the last few seasons actually add up. It's a feeble defense that only makes the attempt look worse by that being its justification, and what's worse, it feels like it's supposed to be the crux of the show's take on love.
And yet, Barney's needling leads to an absolutely beautiful (and beautifully-written scene) where Marshall and Lily update their vows at the altar where Barney and Robin will soon be getting married, and they embrace the idea of growing and changing together and doing their best to love one another whole-heartedly and continuing to renew and update those vows in that effort. That is a wonderful sentiment and scene that deserves to be the ethos of this series and undergirds its best relationship.
What's more, the upshot of Ted's love triangle and all the business with the locket is that Ted is offered what he seems to have really wanted -- Robin offering to run away with him, and he turns it down because he realizes he doesn't actually want it anymore and that what's best for Robin is to be with Barney, and he couldn't live with himself to ruin that. It's a big moment for him, and his turning down what may or may not be his heart's desire for the sake of his friends is a nice beat.
At the same time, while I still think Robin's entirely right to point out all the reasons she and Barney ought not to be together, I appreciate the fact that her big reason is basically that everything Barney does is founded on a lie, and that Barney's big gesture after seeing Marshall and Lily is to promise to always be honest with her, proving it by telling her that Ted found the locket. It's some nice intra-episode writing, even if it contradicts Barney's rehearsal dinner confession that he was probably still going to lie to her. And it even gave The Mother something worthwhile to do her without making her some preternatural problem solver again.
The wedding itself was very nice, feature a great payoff to the ring bear runner, a perfect use of the final slap, and some nice editing and camera work to show the loved ones there watching at that big moment. It's not a perfect episode, but as Ted said, given how rocky the road to get to the end of the aisle was, it was still pretty darn good, albeit perhaps not quite legendary.