I hear what you are saying Jon, but Yirg is a bit of a love or hate bean in milk based drinks I have found. *
Personally it is too bright, especially under 10-14 days, great as a shot but not in milk. *My wife who likes tea, thinks it is great in milk. *And I have had some visitors like it and others not.
As for your situation, it is human nature to get ones back up when you think you have offered something decent only to be told otherwise, even if that person has opened themselves for comment.
Why not reverse the situation and take some of your beans to try next time you are over there. *Once he has tasted fresh beans on his setup, even if he wont admit it, you know it will be better.