helpful to attract contributors from a wide variety of viewpoints -- the diversity is healthy and helps us maintain neutrality. I posit that Wikipedia would be better off with a well-behaved, NPOV-writing Neo-Nazi than without; could such an individual exist?
The hardest thing with Wikipedia is to realize that two editors with diametrically opposite views both still are humans, and still can be reasonable people. Denying that your opponent is also human is a grave error and leads to lots of bad things happening in the world.
For an example of a well-behaved, NPOV-writing nazi (albeit a convert) see Spandau: The Secret Diaries by Albert Speer.