Well, it's personal preference.
Yes, if you decide to mop, each time you open the door, will add to the smoke time. Sometimes that's not a bad thing, you can also add wood to add more smoke if you want. Many like their butts to have more smoke flavor.
I added this mop for those who like to mop.
If you don't have time to add to the already long smoke because of a deadline -- don't worry about the mop, go for a good finishing sauce.