At best, he is severely diluting the brand name that is Henry Louis Gates Jr.--a brand name based in large part on . This is bound to hurt both his own reputation and that of the enterprises he believes in so sincerely.
He is making the brand seem watered down and undesirable. 
mnli hypothesis: He is making the brand seem watered down and undesirable.  premise: At best, he is severely diluting the brand name that is Henry Louis Gates Jr.--a brand name based in large part on . This is bound to hurt both his own reputation and that of the enterprises he believes in so sincerely.