Yeah, I concur. There are a million other ways to test someone's knowledge. Rather than having them write a merge sort (for example), giving them one that eithe

Yeah, I concur. There are a million other ways to test someone's knowledge. Rather than having them write a merge sort (for example), giving them one that either doesn't work or is suboptimal is a much better way to assess their abilities. (Or maybe pick something more real-world than a merge sort since nobody writes their own sorts anymore.) But you get to see how they deal with existing code, how good they are at debugging, and things like that. Those skills are probably going to be used more than writing new stuff from scratch anyway.