There are two types of schedule, which I'll call the manager's schedule and the maker's schedule. The manager's schedule is for bosses. It's embodied in the traditional appointment book, with each day cut into one hour intervals. You can block off several hours for a single task if you need to, but by default you change what you're doing every hour.[Emphasis mine.] Yep, that about sums it up. A mid-morning or mid-afternoon meeting always killed that part of the day for me. Though I did come to appreciate good project managers and others who knew how to run a meeting well (keeping it tightly focused on tasks at hand and making decisions), I still retained a lot of dread for meetings.
When you use time that way, it's merely a practical problem to meet with someone. Find an open slot in your schedule, book them, and you're done.
Most powerful people are on the manager's schedule. It's the schedule of command. But there's another way of using time that's common among people who make things, like programmers and writers. They generally prefer to use time in units of half a day at least. You can't write or program well in units of an hour. That's barely enough time to get started.
Of course, becoming a stay-at-home parent has changed how I organize my time. While working on my novel, I've surprised myself at how well I've trained myself to pick up the most recent train of thought after having lost it due to some child-related task...If I can get the damned thing published, it'll be proof that I'm not kidding myself about how my work habits have changed out of necessity. ;)