All the racing bike frame builders that I know, will categorically tell you that it is not possible to maintain the handling characteristics that their racing frames were designed for by placing the hands above the saddle. This is due to the fact that by placing the hands this high, you cannot have the weight distribution intended by the frame designer. As you claim that you feel that all of your bikes nonetheless handle superbly, this can only be accounted for by three things: 1) Every racing bike frame builder in the world is wrong and you are right 2) You have never experienced a properly set up bike to recognize superb handling 3) you have never ridden a bike in such a way to approach the inherent limits of the bike's handling where inefficiencies become readily noticeable. Point 1) is obviously not the case as you seem to be genuine. Point 2) does not seem to be likely as your posts lead one to believe that you have indeed ridden a sufficient number of bikes to have had the chance to witness superb handling. This leaves us with point 3) the one that I believe to be the most likely to explain your beliefs. I too have ridden bikes that I felt were superb handlers until I took them to the limits of their handling. It was only at this point that the actual characteristics became evident. Looking at an automobile analogy, I own a rather rare early 70's European sports car (only 2 of these cars exist in the US: one in the Larz Anderson automobile museum and mine). In the year that my car was built, the manufacturer won the world rally championship with a very similar car. Needless to say, on the most challenging road conditions that one can find, at high speeds, the car can outhandle almost any other car of the period. When I drive the same car in the city however it would not be considered a paragon of handling. Far from it! I would actually rank it below most econoboxes or minivans. This does not however matter, as the better handling of these other vehicles in these less than challenging conditions would never allow them to 'beat' my sports car under rally-like conditions. Of course, I could add power steering and change the camber of the wheels and improve the city handling, but not without worsening the handling at the limits. Much like what occurs to a bike when you use the 'sit up and beg' stem solution.

When other styles of bikes are ideally suited for such a position and were actually designed to be ridden like this, why would anybody therefore knowingly set up a racing bike in contradiction to what the designer intended? This is why bikes like the Rivendell are so successful: they address the needs of everyday riders like Alan who are enthusiasts but not necessarily racers.