Baseball America has an interesting article about makeup and prospects posted online right now. If you're a subscriber you should check it out.
Obviously makeup and personality factors are important in prospect development. I wrote about this in the book this year in the David Winfree comment. I believe that the next big "thing" that teams are going to find an edge in is in finding new ways to study and measure makeup and personality.
If such a thing can even BE measured. Many clubs use standardized psychological tests, but I'm leery of that approach...perhaps that can be a component but I think something more is needed. Whoever gets a handle on this first will have a big competitive edge.
What I'm talking about is a sabermetrics of the mind...can such a thing be developed? It would not look like statistical sabermetrics...I don't think it is ever something you could reduce to numbers.
Could something like "Jungian Baseball Analysis" be developed? What do you think?