Hopefully this is not too much of a stupid detour from the OP's question. If it is feel free to ignore ;-)

Ignoring the effects of aging on a lens, what are the criteria that determines its contrast levels? Some lenses are famous for it (and it is considered sought after by some) such as a lot of Konica Hexanon lenses and certain Russian ones amongst many others. I presume coatings are a big component. I presume materials are a big deal as is the actual design. Were designers looking to build contrasty lenses or was that just the way they were coming out? Clearly everyone wants a 'sharp' lens but contrast seems to be a slightly different beast and clearly lots of folks think stuff can be too contrasty. Contrast, sharpness and acuity do not seem to be entirely synonymous.

Sorry if these are stupid questions. I have been wrapping my head around lens contrast (and the related issue of the role of the lens in colour reproduction).