They would not be matched in volume at all frequencies. That's becuase different components have different frequency curves. Only if the frequency curve were so flat as to have negligible differences would thhey pretty much match.
Interestingly, most decently made solid state amplifiers and preamplifiers do have relatively flat frequency curves, with negligible difference.
Hence they DO sound alike. So your theory there is correct.
That is also what Aczel says, by the way.
It's common sense if you ask me...if two components measure alike, they will sound alike.

-akhilesh