Short answer: Yes, it's useful sometimes. Longer answer: I always enjoyed these types of questions, and I sometimes solve them in my free time, e.g. Google's C

Short answer: Yes, it's useful sometimes. Longer answer: I always enjoyed these types of questions, and I sometimes solve them in my free time, e.g. Google's Codejam. So when I interviewed I didn't need to prepare specifically for the technical questions. Therefore it's a bit hard for me to say exactly what contribution these questions made to my skills, because it's something I've always done. Also, it's probably not relevant for 95%+ of my work. But once in a while when I do a code review, I see some convoluted piece of code that does something that can be done in 3 lines, like transforming some data from one structure to another. I feel that doing those types of programming tasks helped me find the most straightforward solution in these cases, where other people might only find more difficult solutions. By the way, a skill that is relevant to only 5% of my work is not as bad as it sounds. I'm currently finishing reading a book about presenting information visually. Doing presentations is probably less than 5% of my work.