Something is usable if it behaves exactly as expected.
All non-trivial abstractions, to some degree, are leaky.
Common programmer thought pattern: there are only three numbers: 0, 1, and n.
Indeed one of the best ways to deflect attacks is to make it look like they're succeeding. It's the software equivalent of playing dead.
Listen to your customers, not your competitors.
We just have to come in every morning and somehow, launch the editor.