Now I'm starting to get on overload, but I have to ask anyway, why not overnight? I know Lee doesn't break his kites down as he has a van and a big bag, so I don't think he removes lines from the kite during storage.
I guess when you have a van with plenty of room, it doesn't matter. I have a tiny car with no room thus I need to pack everything up neatly.
In the case of handles. If you use the same length lines all the time you could leave the lines wrapped on the handles, However it does groove into the foam grips which takes a while to recover, especially when cold. Now if you use different length lines, like me, then you either need more handles or wind your lines on the winders.
There is nothing mandatory here. It is really up to each person how they wish to do things.