Here I want to try to give a general overview about the technology of bike components historically and technically.
In the 80-ties it became apparent that Shimano will pass Campagnolo as far as market dominance and size was concerned. Campagnolo did what I never understood, precisely nothing, except to race the retail price to compensate the revenue loss. In 1993 a C-Record group went over the counter for €1250 and the Dura Ace for €850 (in 1993 value) . Today the actual Groups are sold for €1000 (Campy Record) and €850 (Shimano 7800)(in 2008 value).
Beside this, it drove me nuts that the vast majority of riders in the 80-ties were considering the new functionality of Shimano's bike components as an invention or novelty, exact the same generation which helped with their consumption behavior to establish the Italian dominance between 1950 till the mid 80-ties. The reason why Shimano passed Campagnolo is very simple for me, it was the high pricing and weight combined with little to no innovation.
This triggered in me the desire to understand the entire picture and begun to bring some light into the dark age of cycling technology from the 50-ties till mid 80-ties. As a result of this I found a lot of prior art e.g. cotter-less cranks, integrated freewheel body into rear hub, cassettes, index shifter, no dual pivot brakes , hollow crank arms , outboard bottom bracket bearings and more.
From the mid 80-ties it became fascinating, independent minds questioned the traditional way of thinking and boosted the development of lighter components, frames and added functionality.