This drives me nuts; either I'm checking (timestamped no less!) code into the repo, and delivering what I say I'll deliver by the appointed deadlines, or I'm not.
It's not like you can fake productivity as a coder.
Let's be honest, coding is really only half the story. There's lots of deployment, debugging, and maintenance work that is much fuzzier and harder to measure. In fact, if you are actually actively coding for more than half your time, you're either really lucky or you don't have any users yet.