I can tell from personal experience that I only properly understood simpler mathematics when I started learning more complicated one. For instance, in linear algebra, finite dimensional (euclidean) vector spaces became a cakewalk once we started talking about functional analysis. So, I think, even if you don't need that particular stuff in your work, it's still a good training. Also, there has been a pushback against…
That's interesting, I have similar experience. Maybe that just means we didn't learn the original material well enough?