Larry,
>Just my $0.02.
I see your $0.02, and raise it $10,000.
I agree completely with your reasons for reinstating the Reply Button functionality.
About your idea of performance issues being a good explanation -- I wonder: Do the BUTMs still see the button AND the reply count beside it? If the count is there, it's probably not a performance issue that brought this about.
Generally, in marketing and in public relations, I strongly believe that businesses usually benefit from giving customers (and potential customers) more than is expected, and usually LOSE when taking away what was already there. IOW, this decision is full of negatives for BUTM's and the UT as a business.
Most people don't appreciate being manipulated or coerced by a loss of service. I don't see how it can produce anything good.