You need a much humour as possible in a show like this. That was something I leaned from working on the X-Files. I learned so much from Chris Carter, who was the creator of Millennium about serial killers. It was hard to watch, and depressingly dark and I knew for Breaking Bad - a bleak show with cancer and criminality - that it would need to be leavened with humour. So we go for moments of absurdest humour but the moments have to feel real and derive from behaviour that the characters would perform.
So Gilligan is saying that something really bleak needs to be leavened with humor and absurdity. Is the opposite true too? Does something really silly/absurd need to be brought down with some bleakness in order to be full-bodied?
Reminds me of an Apatow quote I mentioned recently: "All great drama has some comedy and all great comedy has some drama."