Thank you for your thoughtful response. I don't have a dog in this fight; I read the original letter because I had seen a brief reference in my news feed to the conclusions of a "Yale epidemiologist" supporting the use of hydroxychloroquine. For me this is mostly a political issue (since I am neither a medical professional nor a patient). I was surprised that apparently only a single Yale-affiliated researcher had come to this conclusion, and I hoped to find either corroboration or disqualification in the Yale letter. The letter and the responses to it here on Medium have only convinced me that I am not qualified to make an evaluation of Dr. Risch's claims. (So for me at least, it's back to square one. There seems to be a fairly substantive political subtext in the arguments--by "political" I mean opinions or assumptions extraneous to or superimposed on discussions of scientific inquiry. "Political" as in "faculty politics" or "sexual politics" for example.)

My objections to your claims were purely argumentative (questioning the nature of your support in the original response). That doesn't mean that your conclusions are not viable explanations, and I appreciate additional information.