Not sure if this counts, but the teaser for TNG "Future Imperfect" (2/5) came on and my girlfriend likes to test my Trek knowledge by seeing how long it takes me to correctly guess the episode based on what happens to be on the screen at the time.
(Riker's birthday and playing the trombone badly are dead giveaways for those also playing at home.)
Anyway, we were leaving without watching it, so she asked me to explain the episode and I never really appreciated how convoluted that episode was until I had to explain it. Once Riker was a 'prisoner of the Romulans' I really felt he should have noticed how easy everything was. And then at the end, Riker and 'son' beam back up to the Enterprise and the kid is never seen or referenced ever again.