Similarly, fizzbuzz is generally massively more useful than whatever silly CS problems people are asking in interviews.

I use fizzbuzz and character counts (histograms) as my primary weapons.

If they pass that since i'm usually looking for iOS developers they get a simple app with poor table view scroll performance and are asked to improve the performance of it.

Edit: This is part of the problem - an Engineer is fundamentally different from a Developer, even if there is significant overlap.