Here’s the background on its construction for those interested,the academic article “Integrating Theories of Motivation”
http://webapps2.ucalgary.ca/~steel/images/Integrating.pdf
Spectacularly uncontroversial really, based on the core and best established parts of the key motivational theories. Due to limiting the theory this way (i.e., focusing on the core elements), it doesn’t cover directly obvious elements like satiation, though really you would incorporate it in value.
If I could redo it again, I would differentiate between goal choice and goal pursuit as expectancy operates differently. However, the public conversation is necessarily limited to reiterating the basics, which is fine, Academically though, it is a bit old hat.
We are working on a software based training program that we can update that is based on our best understanding of goal setting. I like it as it provides a more direct conduit to implementing what we have learned. Actually all inspired somewhat by what Less Wrong is up to.
Love xkcd. Spherical cows and all that. But appropriate parsimony is a desirable feature. Here’s a summary of whether the equation does a good job of summarizing the science:
http://studiemetro.au.dk/fileadmin/www.studiemetro.au.dk/Procrastination_2.pdf
Also, from the book “The Procrastination Equation”
The Procrastination Equation attempts to economically describe the underlying neurobiology that creates procrastination. I will tell you right now; the biology and the math won’t match exactly. A road map of a city, for example, no matter how recent or detailed, can’t represent every corner and crevasse of reality; it skips over details like architectural styles or fire hydrant placement. Judiciously focusing on streets and highways allows the map to emphasize navigation. If this big picture doesn’t satisfy you and you want all the details, don’t fret. The next chapter will give you what you are looking for.
The next chapter discusses it from a neurobiological perspective, which ultimately provides deeper understanding. I think as along as people recognize the purpose of the equation, and that it actually is a step up in complexity from what was previously used, as well as not mistaking the map for the land, it works.