I heard a few faculty suggest that at my school and my reply is always, if I fail everyone, isn't that also equitable? (I.e., if "equity" in final grades is your single goal, adding 100 points to everyone's grade, and subtracting 100 points from everyone's grade will have the same effect.) And of course people react with horror and talk about how unfair that would be, revealing that deep down, they really do believe that grades should be tied to student performance.