Great comment enginous. I want to look into variable interval reinforcement now, as I've been approaching this from more of a research-based angle.
The solutions should be hybrid, though I still believe that better behavior, reinforced by technology, is what will be the most effective. If you have your client reinforcing good checking schedules, that's a behavioral/technical win/win.
That's a great point: technology can be very effective at shaping human behavior.
You might want to check out the Stanford Persuasive Tech Lab's project on behavior design[0], which has some resources about how to use technology to change human behavior.
The solutions should be hybrid, though I still believe that better behavior, reinforced by technology, is what will be the most effective. If you have your client reinforcing good checking schedules, that's a behavioral/technical win/win.