Re: Most significant advance in bike technology for speed?

In another forum, someone postulated that integrated brake & shift
levers (like STI) were the most significant bit of racing technology
ever designed for increasing speed. But that claim met with little
respect. One skeptic noted that there was no great increase in average
race speeds in Paris-Roubaix, Milan-San Remo, Tour of Flanders,
Leige-Bastogne-Leige or Giro de Lobardia since about 1960, including
during the era of STI adoption. By contrast, in the  years 1930 - 1960
average speeds increased around 30%. (Note: That does not mean that STI
is not tactically beneficial. That's a separate issue.)
>
But if not STI, what were the most significant tech developments
regarding bicycle race speeds?
>
Here’s my list:
>
Pedals & cranks, as opposed to scooting a “hobby horse” via feet on the
ground.
>
Tubular metal frames and wire tension (spoke) wheels.
>
Large driven wheels, to give a much higher effective “gear.” (The
Ordinary or Penny Farthing)
>
The “Safety Bicycle” with a diamond frame and chain drive, getting the
rider down lower, to greatly reduce aero drag as well as pitchover on
braking.
>
Pneumatic tires. Hard tired “safeties” had terrible rolling resistance.
>
The handlebar stem, invented by the heroic Major Taylor, to allow a much
more aero riding position.
>
Rim brakes, by whatever mechanism, as opposed to spoon brakes acting on
a tire.
>
Multiple gears, by whatever mechanism.
>
The derailleur, making multiple gears easy to shift, customizable and
light weight.
>
Recumbent geometry in some situations. Recumbents seem to be slower
uphill, but tend to be faster on level or downhills
>
Fully enclosed streamlined aero shells tremendously increased speed, but
at a great reduction in versatility and practicality.
>
Beyond those, ISTM that most developments have been chasing ever
diminishing returns.