Obviously, it's impossible to "determine the ride comfort of materials". At best, one could only hope to see patterns of vibrations that different frames exhibit.

I'm a "ride quality" skeptic. So if I had data from a few hundred bikes ridden from a few hundred miles, and if I saw that bikes with material A tended to have a characteristic vibration spectrum, and bikes with material C tended to have a different, but distinct vibration spectrum, that would at least prove to me that there is a significant difference between A and C... something I suspect is not true.

It might be possible, with another study, to equate vibration data to comfort. The only way I could think of doing this would be some kind of blind frame test - disguised and instrumented frames. After the rider rides for a few hundred miles, he rates the ride quality of the frame without knowing its brand or material. Then, the scientist can attempt to correlate the data to the subjective ride quality...

If you're doing blind frame tests, you could skip the instrumentation, but then you'd miss out on an opportunity to learn something.