I would like to share with you my theory of allocated time.
I am very big on allocating time. It is how I know what I am supposed to be doing at any given time. Most of the time this works well for me.
Earlier today I had allocated Work Time. Then I had allocated Swimming Time. Now, I do have an exam on Monday that I suppose I could be studying for right now. However, this is not allocated Study Time. So even though I am not going to bed for maybe another hour, I obviously can not start studying now, in non-Study Time.
Sometimes I allocate Gym Time. The gym I go to requires you to check in at reception on the third floor when you go in. Now, I could take the stairs, but the stairs involves exercise. And allocated Exercise Time does not start until I am in the gym. You can't do exercise in non-Exercise Time!
Of course, it's a bit harder to enforce the idea that Facebook Time and TV Time do not belong in Study Time. The exceptions that prove the rule?