Dayum, that *is* pretty draconian. When I first started for my current company we had a bi-weekly meeting where we had to list everything we did (minus tiny stuff like swapping a mouse etc) and what "lessons we learned" during the week. Sounds like the same type of manager though I didn't have it anywhere close to as bad as having to account for every 15 minute block of time...
In my projects where we're using Agile development practices, we have a 15 minute "stand up" every day where each member of the team says what they worked on yesterday, what they plan on working on today, and if they have any roadblocks. Makes it more transparent to what each person is working on, and if they're having any issues with what they're working on (like if they keep saying they're working on the same thing several days in a row, somebody can ask if they need help).