One Simple Question About Productivity

One workshop participant asked me recently the following question,

"I've been taught that there are two approaches to plotting out your day: the priority (A1, B2, etc.) system or the process of matching up tasks with certain blocks of time.  Which system is right?"

My response tried to match the best of a FranklinCovey (top down approach, starting with goals and mission) approach and a GTD (bottom's up approach, starting with cleaning up the open loops and stuff that's on our plate) approach.  The fact is, there isn't one method of planning out the day that is superior- what helps me to get important things done is in itself good.

The Problem with A1, B2 Priority Planning
I explained to my participant that this system ignores the fact that some tasks change in their importance as the day goes on.  An A1, B2, C3 method can also get awfully confusing.  After a while, you just get tired of assigning letters and numbers to things!

The Problem with Matching Time Blocks With Tasks
This isn't the silver bullet either as a big block of time could be filled with a meaningless task that simple requires a lot of time.  I would love to prune the trees in my side yard (requiring several hours of labor) but if something else is more important, my pruning would be something of a waste of that particular time.

Here's a much simpler approach to planning out the day: ask yourself at the start of things, "By 5pm, what would I be upset about if I didn't tackle it during the day?"  It's one simple question that works for me and provides a more intuitive method to planning. 

I'd love to hear reader feedback as to other methodologies for planning out a day.