Bicycle Frame Stiffness

It was interesting to note that some of the top end road bikes today
are posting 120 N/mm of bottom bracket stiffness and 90 Nm/degree of
headtube torsional stiffness while fork stiffness is way at at almost
200 Nm/degree. Some of the priciest wheels money can buy, such as
Lightweight Standard, are posting between 90-100 Nm/degree for
stiffness. More here : http://bit.ly/7rOYYT

Obviously, there's no point in getting worked up about stiffness
ratings alone, as there are lots more that gives a bike character.
What according to you mostly contributes to making a good bike? When
does stiffness really matter? In 100 years of bicycle history, lots of
Tour de France level racers have gone by for a long time with"flexy"
steel frames, even broken records (Eddy Merckx...etc.).

-Ron