I'm absolutely amazed that there isn't a single mention of referencing in here. It's by far the most important thing we do in our hiring cycle. Here's what we do, which is a little different: 1/ We'll spend in the order of 5-6 hours with a mid-to-senior hire before we recruit them. We pick one topic from their CV (the project they're proudest of or happiest with), and dive into it in huge detail: everything from the…
This does not mean I disagree with you. We had someone working for us, we're connected on LinkedIn. That person since then switched multiple jobs and I know for a hard fact that he'd never get a job if the company just called people working with him. No way.