I started w/ Office 95 (well, standalone Excel 4.0, actually). To insert cells I'd type "ALT-E-I". To delete cells "ALT-E-D". Aside from cut/copy/paste and simple text formatting (bold, underline, italic) I've never used the CTRL-x shortcuts. I've always just operated the pull-down menus with their accelerator keys very quickly.

Edit: Ahh-- I re-read your comment. I'm not using the ribbon ALT-x shortcuts. I'm using the accelerator keys from the old pull-down menus. No-- those ribbon "shortcuts" are frustrating to me.