For me I would never go to an appointment unless I had just showered but I understand that may not be enough so shower again when you arrive. mainly this is for the comfort of the ladies and just shows respect. I expect them to have just showered as well.
I think XOC has a great policy: the clock doesn't start until after you have showered.
Anyway I guess that is the difference between a top notch agency and the ones local to Houston. I wish there were more of this caliber coming this way.