Id say it depends on the specifics of the job role; In most cases, "the fundamentals" arent relevant at all; they are items on the runtime library of a given high level language of choice. There are exceptions, obviously, but you do not need to be a rocket scientist to maintain an ERP or an e-commerce application; on the other hand, there are plenty of "hard problems" where computer science is also mostly useless, because the steepness of it is advanced math, not algorithm design.