All I can say is my own personal experience, since I'm new to snakes - I've only had my Cal. Kings for about a year now. My female has actually gone into blue, come out of it, and not shed at all before - she had a perfect shed the next time she went into blue, and has never had anything but a perfect shed... when she did.

My male has spent over a week in heavy blue before, then didn't shed until over a week after coming out of it. Perfect shed - he's never had any other kind.

I have no explanation... just my own experiences.