I understand the historical and current purpose and meaning of CTRL+ALT+DEL. I, too, have been in the industry for a while. But the fact remains that the general feeling of CTRL+ALT+DEL is a combination to be used when something has gone wrong.
To attach that stigma and historical baggage to something used to simply signal your UI shell that you want to reboot, logout, or shut down is unintuitive to uses moving from the windows world to the Linux desktop. You and I perfectly understand, because we're advanced users. My girlfriend simply wouldn't get it.