Something that has always bothered me about "The Last Roundup"--
AJ drives the stagecoach across the railroad tracks a split second before the train rushes over the road, leaving Twi and RD trapped on the other side. The stagecoach ponies say in chorus, "Lady, you are trouble!" and gallop off with the coach, leaving AJ standing there feeling smug because Twi and RD can't get at her. But they solve the problem by leaping over the train, dragging the wagon behind them through the air.
That train is only about 16 coaches long. Why don't Twi and RD just wait ten seconds for it to pass, and then continue chasing AJ? And why are they still dragging that empty wagon, when Rarity and Pinkie have fallen out back along the road somewhere?
Also: why aren't RD, AJ, and Twi worried about Rarity and Pinkie? Why don't they go back to find them and make sure they're okay?
The more I think about all this, the less sense it makes.