> if X applications don't care about working remotely, then they *DONT*, because they do too many round-trips, [...] I have tried to use X remotely a few times, but it simply isn't usable for most things other than emacs and xterm.
On a LAN this is just plain wrong.
Not so long ago people working with dumb X11 terminals on Ethernet 10M. For sure they were not playing games nor using Eclipse; that does not mean they were using only emacs and xterm.
Not later than this morning I used this over encrypted (!) X11 forwarding: http://www.methylblue.com/filelight/
It worked like a charm, just like thousands of other X11 applications. Out of curiosity I just tried: gimp, firefox, and OpenOffice and they all work flawlessly on my LAN. I did not even had to get rid of the encryption!
The reason why X11's networking is not so much in use nowadays is just because a powerful PC is now cheaper than a dumb X11 terminal. It is NOT because every single X11 framework is badly designed and wasting thousands of round trip times and cheap CPU cycles.
For sure there are plenty of cases where X11 networking is irrelevant. There are ALSO plenty of cases where it works perfectly thank you very much.