nonoise,
I don't think your analogy quite gets around my point.
If you had a richly detailed Ansel Adams photo, and took a picture of it with a newer camera producing a new version, every bit of detail you swoon about when looking at that photo speaks to the quality of the original equipment used to take it. The new camera can't introduce any more information than was already there in the original photo. So long as we are talking about reproducing the original photo with fidelity (as opposed to taking new photos), it's the information on the original photo that is the only thing left to impress us.
Similarly, every time an audiophile with expensive cables swoons over the finger picking on strings, or delicate reverb trails in his system, he is swooning over the information conveyed by the original cables used for the recording. The cables used in creating the source didn't need to be one "better" (and more expensive) than the one preceding it. If cables used for the creation of the source (again...LOTS are involved along the way) were THAT detrimental to the signal, the sound reaching your system would be crap, whatever cables you used to try and get that information back. But that's not the case - you will still be amazed at the signal you are listening to because non-audiophile cables - many of them one after the other - are fully capable of preserving the detail you are hearing. A well constructed cable should continue to reproduce the full signal fed to it, and on to the next (properly chosen) cable.
Your appeal to mastering eaking out more detail is a red herring here: that's a function of playing with fequency response/eq/compression to emphasize whatever the mastering engineer wishes to emphasize - or "fix" by re-balancing the signal. The engineer would still be using only the information available to him that made it through the original cables used for the source.
