update current buffer with gist

[pinggit]

with this wonderful plugin one nice workflow is to put GistID 123 in a file, so when I want to update the gist I can just do : Gist.
but I found it not so smooth to use the gist to update current file.

say in machine 1 I edit the file (with GistID xxx in it) and do : Gist, so gist is update.
now on machine 2, I open the file (with old content) and I want to have this file updated from gist. is it possible to just do sth like : Gist -u to update current file?
which will be great!