Anecdotally, when I use simple command idioms like ctl-tab to change tabs, alt-tab to change applications, or press alt in an application to bring up the single letter shortcuts for navigating menus my students are blown away.

I have to actively teach them how to use and navigate file folders, how to make an appointment in Outlook, and other fundamental user operations. I don't blame them, I blame the developers primarily of browser based cloud apps and OS's.

Edited to add: this includes using ctl and arrows to move by whole words, etc. fundamental stuff in the apps they would have been using since a young age. Not to mention how to use the fn key to access the other functions of Function keys, and fn-esc to switch the behavior globally on their laptops.