What about the scenario of "I can't be bothered to declare the variable and I'm the only person who's going to see this mess anyway"?
Most people will agree that it's best practice to declare variables first, so I don't feel particularly strongly that there should be a feature to help cope with undeclared ones. An "Add declaration for this word" could be a time-saver, though the IDE can't mind-read you and declare it exactly where you want it. Unless the implementation of a feature like this is really quick 'n' easy, perhaps it would be better to concentrate on the more important requests and bug fixes.
Most people will agree that it's best practice to declare variables first, so I don't feel particularly strongly that there should be a feature to help cope with undeclared ones. An "Add declaration for this word" could be a time-saver, though the IDE can't mind-read you and declare it exactly where you want it. Unless the implementation of a feature like this is really quick 'n' easy, perhaps it would be better to concentrate on the more important requests and bug fixes.