the golden mean of this quality: that perfect middle spot, representing the exact amount of the quality in question
The phrasing here again manifests Schur's Error About Virtue: A virtue is a character trait which Aristotle suggests we can usefully represent as "located" at the midpoint on a continuum of ANOTHER quality or qualities. The quality that defines the continuum isn't, say, generosity (running from a little to a lot); it's something else, like tendency-to-give (running from too little to too much). "Generosity" and other virtue terms are reserved to identify the traits that allow us to choose the mean between extremes well.
So in Aristotle's sense, one can't technically be "too generous." If one tends-to-give beyond what is wise, that is not generosity, but overshooting virtue; it might be called extravagance. Still, setting aside the more rigorous language of virtue theory, when we're not doing ethics, we might describe an act that misses but aims at generosity as "too generous." I'd argue that it makes sense as a matter of courtesy to call someone like this "too generous" rather than just "wrong."
