I agree. In fact finding an explanation of pretty much any significant mathematical concept that strikes that balance (across the broad range of individual tal

I agree. In fact finding an explanation of pretty much any significant mathematical concept that strikes that balance (across the broad range of individual talents and backgrounds) is time-consuming or difficult. Which is why a significant chunk of mathematics research effort and funding should go to making such explanations less time-consuming and difficult. IMHO. It may be as simple as a vetted compilation of explanations for a single idea so the individual can find the ones that work for them, or formal development of new explanations. What’s more significant: a new incremental result in some obscure corner of math, or 100M more people understanding what an eigenvalue actually means? Or a new explanation that makes a concept more relevant in an entire application area?