I'm over in NYC on a brief work trip and whilst here managed a catch up with Dan. One of the things we ended up talking about was this great piece on the chokehold of calendars which makes a simple but powerful point about how calendars can become a 'record of interuptions' rather than a useful tool for managing time.
The sentiment of the post reminded me of Paul Graham's essay (that I also mentioned here) that talks about the difference between what he calls a 'maker's schedule' and a 'manager's schedule'. Whilst 'makers' (people who create stuff, writers, programmers etc) prefer to set aside longer periods of time (at least half a day) since that is what is required in order to progress or complete a project, managers often segment time into one-hour slots. The 'managers schedule' may involve several hours being blocked off to complete something, but the default is typically to change what you're doing every hour.
Graham's point is that a meeting for a manager is usually a case of simply finding a suitable slot but for someone on a 'maker's schedule' it can be disastrous since it breaks up a morning or afternoon into time chunks too small to do anything productive with. Problems can arise when the two types of schedule meet and those on a 'manager's schedule' can easily end up making everyone else 'resonate at their frequency'. Both pieces are a good reminder about the sanctity of productive 'doing' time and just why we should work hard to protect it.