he himself said, rather emphatically and dramatically, that he would rather deinstall then restart
Saying something when you are frustrated by a problem, self inflicted or not, is a little different than just replying to say 'uninstall and go way', though.
he dropped a spell himself because he wasnt paying attention.
The skillbar is (currently) inconsistent, though. You can drag and drop spells off the skillbar and it merely removes the shortcut, which can be re-added. It wouldn't be unrealistic to expect the same thing for scrolls, and if there are multiple windows open or you are in a cluttered area, it is possible to miss the change in cursor or the actual item being dropped.