I think the distinction here is between "I understand that X is a solution to Y", vs. "I understand that X is BASICALLY a mashup of A and B according to scheme

I think the distinction here is between "I understand that X is a solution to Y", vs. "I understand that X is BASICALLY a mashup of A and B according to scheme C." A lot of times, people reach for X when they have a vaguely Y-ish problem, when that's actually inefficient or overkill, and/or you could easily validate if X would actually work by manually trying out A and B by hand. In addition, there will be times when X cannot directly solve the version of Y you have, but there are simple ways to tweak A or B such that now you do have a solution to the problem. So you can become much, much more effective at solving Y-like problems by understand the the building blocks behind standard solutions.