- Will you marry me ? - Yes.

Maybe, in my view, the best ending for this couple exists in this episode with this song lingering.

Robin is the one that changed Barney's whole life and made him a real legend. And Barney is a genuinely good liar, lying to anything except his love for Robin.

I feel the proposal with Let Your Heart Hold Fast is perfect for How I Met Your Mother, not giving a shit about the fucking actual ending that pissed me off.