[zmmmmm]

I agree, I think it's mixing up cause and effect.

Especially how it is phrased with "feel obligated", it's clear these are people who are conscientious about their productivity and most likely set a higher bar for their output. It's hard to think their out of hours work is causing their loss of productivity, rather their work environment is causing it and only the people who feel bad about it (ie: would report that their productivity wasn't adequate) actually work longer hours to compensate.