I would be interested if you can present a specific piece of code that would be really confusing to a programmer who does not have experience using languages with lexical closures.  I didn't follow the same order of education, so I never really experienced an a-ha moment like that; they seem like a simple language construct to me (although I can definitely understand how it would be hard to recognize their utility without having experience using them.)<p>(I can understand how code passing around anonymous functions can be confusing to people who don't use a language with first-class functions, but I would figure they're confused by the logic, not by the closures.)