I have not turned any coffee mug sleeves so I can't help you there.
I have rough turned many boxes and I turn them with a box shape in mind so it is important to think about which box form you are going to turn before you rough.
I probably rough to 3/4" but don't really measure. I don't coat them with anything but I do tape them tenon end to tenon end just as described in the Raffan book. I just let them sit in a bucket or on shelves for several months or longer. On occasion I will use a moisture meter to see how dry the wood is. Here it is very humid and seldom does the moisture level get below 10%.
I may be getting a little older physically but mentally I'm still tarp as a shack.