Let alone the "business value" of an individual programmer's commits.
I think "business value" is a particularly bad phrase because it sounds like something that can be quantified and has a clear implication about which class of people will do the quantifying (namely, business people as opposed to technical people). In reality, it can't, and the term is really about power dynamics within companies.
I don't know why you say business value is actually about power dynamics, unless you mean that people use the term to promote their pet projects. If so, I think that has more to do with human nature than the term "business value."
If it makes money, it has business value, in my book. If it makes MORE money, it has more business value.
Actually it might be the ONLY measurable thing in the whole discussion.
For business value to be measurable means you have a function M(x) that maps x to money. The trouble isn't with the range of that function, it's establishing what the domain is and how to compute M.
People often talk about business value on software projects as if they have such an M when they don't. What they have is an imaginary M whose domain is "what I care about" and whose output is "what I want to believe". Such discourse is dysfunctional.
The truth is that you have M for the business as a whole and maybe for specific products (though I can cite cases where even that was dubious) and it typically breaks as you try to get finer-grained.
