Contrast Collar, Matching Pocket Square and Tie Acceptable?
This seems like saying "My car has traction control. Will that mitigate the damage if I drive into a tree?"
I kind of like contrast collars (on solid blue shirts or blue shirts with a white stripe), but I think if you were looking for a way to simplify things then I'd suggest this: always wear a white PS with a contrast-collar shirt.
I think it does, though. In a purely aesthetic way, is it less boring? Sure. But it still makes the wearer look like an unsophisticated dresser. That's the pitfall of contrast collar shirts, really -- they tend to be used badly by people who are new to dressing in suits, who end up preening in them. Add in the matching-tie-and-square -- a pure-D rookie screw-up -- and it would scream "trying too hard."
That second part is plausible, but then it can be used to argue that with costume, almost anything goes. Also, pocket squares themselves are closer to costume than they used to be. Regardless, after the obvious first choice of white pocket square, it becomes harder to coordinate a square with a white contrast collar (and tie) without doing a color overload.
For anyone who does not know how to coordinate pocket squares and ties or cannot be bothered to learn how, they should just stick to white linen or maybe cream silk (or alternatively avoid pocket squares altogether). Matching ties and pocket squares look cheap and tacky and make the wearer look like he doesn't know how to dress. I don't see how wearing a contrast collar would make a combination that looks bad any better.