A live programming interview measures a candidate's performance in interviews, not in programming. This is because people are very bad at evaluating others' skills; those with more charisma end up winning.

I remember participating in a vote to choose a company's best employee. Whoever came in first place earned a ton of proactivity points. What? That person's work made any proactivity impossible. I asked a friend who had given this person top marks why, and he asked, "What is proactivity?" Charisma wins.

I've worked with several seniors who were terrible programmers, but... they were good, excellent in meetings... and others who threw barbecues for their bosses...

Sure, you can advance in the company and get hired by being very good at what you do, but that's not the rule in my experience.