> Does this approach ever work?

Maybe. I think this approach might work better for students applying for summer jobs mowing lawns, working in snack bars, movie theatres, etc... than people seeking professional long-term careers.

>Can these job applicants be swayed into a more effective behavior, such as tailoring the job application, or should they really be declined on the spot?

**Normally**, I'd say "Why do you care?" because you're not their mother and it's not your job to help them get a job and generic resumes will work against them. *BUT...* I'm guessing you asked this question because some of the generic resumes you read piqued your interest enough that you want to give them a second chance to write a better resume. If they're good enough to warrant some interest, why not invite them in for an interview? It sounds like they got your attention *despite* having a generic, mass-mailed resume, so it might be worth following up on.