Okay, so he got the interviews, but did he pass them?

In the place I work for, when engineers are going to conduct technical interviews, the only preparation material they are given is the candidate's resume. So we try to ask questions based on their experience in the places they claimed to have worked for. It's not super hard to realize the job description in the resume is embellished once you start asking questions, but yes this is not fool-proof. Still, the best candidates will often have very interesting discussions about challenges they had in their previous jobs and be able to properly articulate what they did and why and how. If you're gonna lie, you better back it up very well.