As far as the field “Human Theory” goes, I'd say it's most closely related to behavioral economics. I'm not really sure. I can't claim to know anything about this topic (except that what I've seen from Dan Ariely is very interesting).

Human Theory isn't really a topic of study that's found in history or books. It's just about communicating intuitions about the human experience and learning from it. So I'll say it's brand new. You can read a lot of stuff in books, but to me that pales in comparison to reflecting on daily experiences with people and discussing with others.

First question: “Does the highest possible combination of commitment and happiness lead to the highest performance?”
I'd say absolutely but you need to take time into account. Over time, these forces regulate each other. A fanatic that is over-committed to the point he ignores other responsibilities/necessities will soon find a huge reduction in happiness. Similarly, someone that is incredibly happy will have a hard time finding a need to stay committed to an ideal condition. Think rich guy on the beach who has it all. Until he gets bored, he's perfectly content to sit by the beach. However, he'll eventually find himself confronted with lack of purpose and mission and will have his happiness adjusted appropriately.
As I see it, the highest level of commitment and happiness does lead to the highest performance. They regulate each other. If one is out of balance, in time, it will be corrected until the individual finds the sustainable maximum.

“Not everyone has the awareness of resources or the judgment to appropriately adjust their ideal condition.”
Absolutely. You've pointed out one distinction that I left unclear in my essay: the individual may desire a change and needs to in order to be happy and perform, but won't necessarily make the change (don't know what to do or how to do it.) If everyone was able to adjust accordingly, we would be surrounded by happy people.
Unfortunately, we are not.
The important point I think you make is that “doesn't switching to a new ideal condition require resources (mental, financial, etc.)? In which case, performance does in fact depend on resources”.
In the case you presented, a child stuck in a bad position, I'd say “maybe.” But probably not. It's a tough case to analyze because a child develops quickly and is actually moving very quickly towards many ideal conditions, learning and gaining abilities.

In general, the decision comes down to this: find a way to be happy, or not. You need absolutely nothing to commit to something and engage in it. Some unhappy people don't know what to do, don't make any decisions, and stay the same. Others will find something to commit to until they gain the happiness they desire. It may start with committing to finding something worth committing to.

The major exception to this is likely people that don't have their basic needs fulfilled (food, water, etc.) But, I don't have enough experience with this situation to contribute very much.

First of all, I think you have made some decent insights into what you're calling “Human Theory.” Though as a side note, I think it would be helpful for your readers to have some sort of introduction to the field, if you plan on continuing this work. Even just a brief lit review would help. Whether or not they called it “human theory”, surely there are great thinkers before you who have pondered human behaviors. And grounding your thoughts in intellectual history gives credibility to what you're saying. But that's just a suggestion.

Back to your equation of performance, I think you're onto something. However, I am curious as to how you will extend the equation. The next logical step (to me) would be how to use your equation to optimize performance, taking the theory to a more dynamic and practical realm. It's been a while since I've taken a math class, but I believe in your current equation the way to increase performance is to increase either commitment or happiness. I maintain that this is not always possible, or even appropriate. What I mean is, “optimal” performance is not always attained with the highest possible commitment or happiness. Can't one be overcommitted to the ideal condition – possibly to the deterioration of the person's overall condition?

And from the same idea, I think you are missing an element that would allow someone to change their happiness or commitment level. You seem to brush off resources as unimportant, saying that we can adjust our ideal conditions to fit our capabilities – but I don't think you can take for granted that everyone has an awareness of these resources and their personal capabilities to make the appropriate judgment.

For example, when I was 2 years old, I stuttered so badly that my parents took my to a speech therapist. Because I had not uttered even a simple sentence, they assumed that I was intellectually below average. As it turns out, my language comprehension was well above average, but still I would not speak. The therapist concluded that I was so determined to articulate my thoughts exactly as I wanted, I would not speak until I could fully develop a perfectly complex sentence. In other words, where most children say “I see dog,” I refused to settle until I could say something like “look mommy! I see a little puppy across the street that I want to play with!” (you get the idea). My point, though, is that because I could not articulate the complex sentence, ie achieve my optimal condition, my happiness and commitment plummeted until I was so frustrated with my performance that I would just stutter and not even attempt “I see dog”. I was miserable. That's because I wasn't aware of my resources, and aware of my capabilities, so I could not adjust my ideal condition.

Forgive me, I've been recently spending time with my baby nephew, so language acquisition is the first thing that came to mind. But I do think you need to account for this dilemma, as it would be possible for any stage of human development. You cannot simply take for granted that someone has the appropriate knowledge to adjust their ideal condition.

I enjoy your site! Keep writing!