I wonder if file fragmentation is important here - I guess the more it's copied the more likely it is to be fragmented.
Anyway another yet more 'proof' that "bits ain't bits"
I note you put proof in quotes so I'll go easy

1) Fragmentation happens where there is not enough contiguous space on the disk for the file to be stored all in the same free space. For audio (even Video) data rates and file sizes you can discount any fragmentation issues.
2) The ripping process is variable as CDs are not perfect and read error can happen. wich is why ROM drives are better as they allow the data to be re-read and checked. However, once the validated ripped data is on a computer drive then bits are bits, there no question about this.
The transfer of this data in an asynchronous manner (copying the file, sending via LAN packet) is bit perfect, so again this is fine.
It�s only when we have to stream the data as bits that we start to running in to temporal issues ie jitter and it commonly agreed that jitter reduction is a large factor in improving AQ.
Regards,
Carl