WRT the physical security argument in favor of disabling sysrq, my assumption is it's more aimed towards defeating quick-n-dirty mischief style abuse. Ages ago

WRT the physical security argument in favor of disabling sysrq, my assumption is it's more aimed towards defeating quick-n-dirty mischief style abuse. Ages ago I worked with a small team of young sysadmins who would often cause trouble for one another abusing things like sysrq, or poorly configured XFree86 instances without DontZap enabled (ctrl-alt-backspace termination, to a shell when startx/xinit is being used). Most of the time nothing malicious was actually done. But when you return to your screen-locked X desktop to find a fullscreen VC with a root shell blinking back at you and an empty history, guess what you'll at least have on the back of your mind for the rest of the workday?