asked if Congress should consider enacting rules for physical and mental fitness to serve it would have been a "Fair" question...I'm surprised it took you all these posts to finally get that.
Even if the reporter had framed the question fairly, in his position as Minority Leader it would be poor judgement to agree without conferring with his caucus. BTW, Democrat Rep. Perez from WA has begun discussion on that issue...we'll have to wait and see if GOP Reps join her in seeking legislation.
We both should agree that this is a very difficult and thorny issue...nonetheless, it's worthy of further discussion.
Oh, and as to your comment on Biden...I was very impressed with his cognitive and physical abilities during last year's SOTU Speech...and later, after JB 'Ran out of Gas' in the debate, I concurred that he needed to step aside...which, to his credit, he had the intelligence and courage to do. Would that the current maniac in the Oval Office would do the same....but of course he's terrified of leaving the "safety" of the Presidency and being held accountable for all his truly High Crimes and Misdemeanors.