First, I called him "Ben" without thinking about it. He happens to be a friend of mine, we talk on the phone and calling him Ben seems to be natural. It wasn't intended as making thing "personal."

As for the rest of your points, argue them with Dan Sugalski :) Incidentally, that link points to a concrete example of something that might satisfy tilly's desire to see a problem for which MMD is suitable.

Oopsie. The code silently fails.

That is an argument for prototypes on methods, not for MMD specifically.

As I pointed out earlier in my post, my discussion was about both MMD and proper argument handling. To my mind, you can't have the former without the latter. And I agree with your concerns about B&D. I, too, don't like B&D, but to my point of view, properly implemented MMD could let me having sanity checking without forcing any sort of B&D. See Perl 6's ideas behind MMD for examples.