Confusion about Ports and options framework

[Zachary Kline]

Hi,
    I've read through the sections of the handbook quite carefully, and 
haven't quite found what I'm looking for.
    To be specific, I've no plans to install X11 or anything like it on this 
machine yet.  I may do so in the future merely to see how accessible Gnome 
and such are, but not now.
    I note that /usr/ports/editors/emacs has several environment variables 
which can be set, such as WITHOUT_X11.  I can set these just fine, and don't 
get any X-related dependencies.
    However, if I were to use something like Portmanager, Portupgrade, etc, 
is there any way I can keep it from downloading these as well?  On the 
subject of port managers, is manual port installation the prefered method of 
doing this anyway?
Thanks in advance,
Zack.