[talentless]

I think this is exactly right. It is easy to measure 'time in chair', but that isn't a metric of productivity. Productivity is harder to measure so 'time in chair' is often the substitute.

When you work remotely you don't have 'time in chair' as a proxy for productivity so you have no choice but to prove yourself through your output.

When in an office you can stare at the wall all day and have it considered "work".

Working remotely isn't for everyone. Some people do not have the self-discipline. Don't allow those people to work remotely or don't hire them at all.

There are other benefits to working in the same meat-space: culture, easy collaboration, etc. I don't believe pressure to produce results is one of them. I also think that most of those advantages are disappearing or gone with chat, email, skype, google hangouts, and other collaboration solutions.