content-type and name parameter

I have a question about the use of name parameter in MIME header content-type.

Such parameter is optional in most of the media types, and
(correct me if I'm wrong) it's optional for application/msword,
application/pdf and similar media types.

Also if it is optional it seems that most of desktop e-mail clients 
include it when generating one of such content-type.

So I wonder if there is any client (desktop client for Windows, Mac, etc..)
that doesn't include the name parameter when creating a content-type.

Could someone rely on the presence of such parameter to develop some software ?
I think no, but your opinion is very much important for me.

Thank you,
/Francesco