You are trying to have a single, exposed filter in Drupal Views which allows you to apply the value against more than one field to filter results.
You've tried Views PHP, CustomField and similar tactics. You've considered using some sort of jQuery function but know it's relatively hacky and possibly unreliable. You're about to give the whole idea the boot.
You've looked everywhere but cannot find a solution.
Now you have.
(Yeay - that really works! Yeay...)