i had always assumed it was just something caused by health issues, but i'm really digging all the speculation here because it sounds too awesome for the show to pass up

>Judging by the subtle intensity of their scene together we
>may even see that happen this season. Cause you know Mike
>doesn't want to let Tuco out of jail, and you know he has the
>ability to fuck uncle's world up, and you KNOW Mike doesn't
>take this type of shit or bribery from anyone.
>
>So we'll see. But it's an interesting theory.