About Goldratt’s Critical Chain: When I was in college, I noticed this phenomena too. There is one twist though: creative thought (What's the best way to solve this problem? What should I write my term paper about?) is more compatible with an interleaved ABCABC pattern of work than a straight AABBCC pattern.

What I mean is, that if you need to think creatively to solve a hard problem, you are more likely to hit a solution if you think about it for a while (work on A) and then go on and work on something else (work on B), leaving room for a flash of insight.

However, B usually is equal to "take a shower"*, or "walk the dog". If you try to make your B task equal to "solve this other hard problem", you just get gridlock, and block out any chance of having an "aha!" Note that interpersonal interactions are a known hard problem of human life! *See Dilbert, et. al. Nice preview, btw. How on earth did you do that?