>didn't love the accountant analog. Part of the problem, aside from measurement, is impact. A great athlete can make outsized impact. And while I'm sure a horrible accountant can make an outsized negative impact, it's unclear to me if a great one can make an outsized positive impact. What would that impact even be?

Are you kidding me? A great athlete can do no impact at all. Except if by impact you mean get people to watch him perform. Other that that, it's pure show, nothing productive comes out of sports.

A great accountant on the other hand can save his clients millions or billions of dollars through (through tax loopholes for example, avoiding costly mistakes, offering good advice etc).