The magic tuck in only works if child stays in the bed that said tuck in was applied to. So if, for example, he decides to lay down in your bed and you magically tuck him in and then later transfer him to his own bed, he will get up at 1am and decide to come curl up in your lap to fall back asleep requiring one pregnant mommy to try and get up from a reclined position with a 37lb toddler dead weight in tow and stumble across a land mine strewn boys bedroom trying not to break an ankle on toys and get him back in his own bed to properly reapply said magic tuck in.

lesson learned.