Technical question : 3DsMax Smoothing at the end of process

Hello,

I didn't find any technical forum about 3dMax at the main page,
I wish my thread do not bother the General Discussion

I have a question about smoothing, my mentor always said that smooth
as the final process of work after you rigged and skinned the model.
But I have some question that not answer yet (he is doing
big project lately).

I built model which covered by armor, and I deleted the inner part of body
in order to minimized the count of polygon. at the beginning of rigging process
I attatched every part into single object, which confusing me later is :

after Rigged and skinned the model I need to detach some part to smoothing
them (like face, cloth and gloves part), then finally attatched them again
as single object... is it going to break the bones, and skin or even the animation
movement that I already applied ?

Sorry for my english (I am trying)

Thank You Very Much
Hope the ansewer come ASAP