I want to validate what I believe is true - that when successful sales
people are put into poor territories or given hard to sell products,
that they are able to perform exceptionally anyway. That when you are
good at selling the circumstances of economics, territory or product
don't matter that much. I want a research paper or two on this

Hi thechangecoach-ga

Noticing the 'Change Coach' in your handle, you may be interested in
approaching this from the point of view of the personality/behavioural
factors which cause each unique individual to succeed and fail
differently, in different environments and with different products. 
For example, 'Optimism' or 'Positivity' has been proven empirically to
predict sales success. Martin Seligman writes about this in his books,
e.g. Learned Optimism.

Tools like this: http://www.insightmatters.com/Personality_Tests.htm 
profile such traits and others very richly, so that a trained coach
can then help a salesperson to leverage their areas of 'fit' with
their sales territory, and develop or work around the personal
tendencies which detract from their total success.

All the best,
Delisay