Come on, how is Ctrl-Alt-BkSPC different from Ctrl-Alt-DEL? In fact, Ctrl-Alt-DEL is much closer to the arrow keys on most keyboards. If you're going to complain against Ctrl-Alt-BkSPC zapping the X server, you should at least present a strong argument against it.
Here's one: people often type Alt-BkSPC because of GNU readline defaults, and emacs defaults. Ctrl and Alt are next to each other on many keyboards, and thus easy to press together by mistake.
Now, THAT is a good reason to revisit using a single press of Ctrl-Alt-BkSPC to zap the X server.