I've done it. If I run really high overnight, I sometimes have to get up to go to the bathroom. I test, and if it's high enough I take an extra shot. (I'm Type I.) To do it requires that I first awaken because of the polyurea.
The trickiest (although very rare) event is when I suspect I'm running very high overnight because I've already crashed and rebounded. (I think that is called the Somogyi effect or some such.) That is a mess.
Have you heard of the development of an inhaler to replace shots? I heard last year it was being tested.
Interesting. I would think that it would be dangerous administering insulin at night, especially regular, since the person would be asleep and possibly unaware of any precipitious drops (Somogyi effect). However, if the glucose levels are high, you wouldn't want to drop it too drastically, so I guess you could either give a longer acting insulin that would peak during waking hours, or a smaller dose that would bring it down gradually. I guess I should have instead said "I would think that the norm for diabetics would not be to wake up in the middle of the night to receive insulin".