100 Things You Should Know About People: #19 — It’s a Myth That All Capital Letters Are Inherently Harder to Read

http://www.blog.theteamw.com/2009/12/23/100-things-you-should-know-about-people-19-its-a-myth-that-all-capital-letters-are-inherently-harder-to-read/

While a lack of research is cited I think the comment we are used to mixed case therefore we are faster with mixed case says it all.

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