Yeah, illustrates nicely why it's not a good solution.
Of course, how we do things is largely a matter of habit and standards. Not entirely - for instance, there was solid usability research coming out of Xerox PARC showing that mouse-based editors were better than keyboard-only ones, and nonmodal editors were better than modal ones. Emacs was made in part in response to that research. But for the most part, one way of doing it is as good as any other.
It's just that vi and emacs (and wordstar!) lost that battle ages ago. Your browser, your IDEs, your widget libraries, your anything-that-isn't-actually-vi-or-emacs, use a standard based on IBM's CUA standard + Microsoft's defaults for cut-copy-paste (inherited from Apple). Odds are this very web from supports the old IBM shortcuts for cutting and pasting, (ctrl-insert, shift-delete, and shift insert), even though no one ever uses them.
You can keep forcing them to conform to obsolete standards with plugins if you must, but that is IMHO creating more trouble for yourself than it's worth,