Excellent "How I Met Your Mother" tonight- you can never go wrong with an entire episode based entirely on flashbacks and flashbacks-within-flashbacks, and great to see Laura Prepon again, playing the sort of nightmarish college girlfriend that every one of us had at least one of.
Two big continuity holes, however: One, if Marshall forgot his pants, what pants did he wear on his way from home to the gym? And two, in the flashback to college, when the characters are going to Wrestlemania, Marshall is dressed as the Ultimate Warrior. It's already been established that the characters are in college in the late '90s; the last time Warrior participated in WM was 1996, at Wrestlemania XII. The event took place in Anaheim, Calif., more than 3,000 miles away from Wesleyan College.
Plus, when Robin talks in her sleep, it's hockey play-by-play.