Surely a 15 minute phone screen at the beginning with an HR rep would help thin the field, no? Just something quick for them to show that they know how to act appropriately, dress professionally, show up on time, and speak the language. Plus it provides an opportunity for the HR rep to show a roadmap of the process and the candidate an opportunity to ask broad details in case they need to back out.

Caveat: I hate the concept of HR and the phone screen is an excuse to waste their time instead of mine. Also none of this applies if you have < 100 employees.