Except when something takes a different time than needed, it makes a domino effect on the calendar. And even if something takes less time, it has a disruptive effect on the calendar.
Writing a piece of documentation (no code, nothing can compile or crush) can not be estimated to take precisely 30 minutes. Solving a bug may take a minute or hours, in case nothing goes unexpected (if it does, it can be days or unsolvable). So, especially in the latter case, I cannot imagine how the calendar is superior to to-do lists and sprints.
In sprints, single estimates and be wildly off, but we can still work reliably with averages.
Writing a piece of documentation (no code, nothing can compile or crush) can not be estimated to take precisely 30 minutes. Solving a bug may take a minute or hours, in case nothing goes unexpected (if it does, it can be days or unsolvable). So, especially in the latter case, I cannot imagine how the calendar is superior to to-do lists and sprints.
In sprints, single estimates and be wildly off, but we can still work reliably with averages.