参考になるかどうかわかりませんが、一応、紹介しておきます。

Posted by DoMiN8ToR on Thursday 25 October

As we reported yesterday there is a new function in CloneCD that is
described as: "Error-free data sectors will be re-generated during
reading. This new feature greatly improves the quality of the copy."

Starting a rumour on this site seems to be the fastest way to get
an answer, because the author of CloneCD has already replied on
this issue, unfortunately not to us, but here it is anyway (Thanks
to Chronic):

This "regeneration" feature seems to cause a lot of confusion, so
I should clarify what it does:

When reading a data sector in any "RAW" mode (2352 bytes/sector
and up) you get 2048 bytes user data + "other stuff" like ECC/EDC
(Error correction information). CDs tend to get "scratchy", so
the error correction is used to check and recreate the 2048 bytes
user data.

Since V2.x CloneCD has e ECC/EDC correction in Software (cool
feature! I hope you are clever enough NOT to disable it in the
FES settings), which could "repair" some errors on the disc.

Now I hear you scream: "Hey, you are not making IDENTICAL copies!"
Well, yes. But I make "better" copies, so who cares? If a sector
has errors which CAN be corrected, they SHOULD be corrected BEFORE
the copy is made. Otherwise errors on the original would be on the
copy + the errors which may happen to be on the copy.

CloneCD 3.1 goes one step further. If a sector passes the CRC check
(User area checksum matches) the ECC/EDC is regenerated. Why? It
might be possible, that an error happens to be in the error correction
part of the sector and is therefore unnoticed. If later on the copy
an error is added to the user area, the error correction might fail
to repair the error because it might be corrupted, or the CD-ROM would
need retries to read such a sector. With CloneCD 3.1 you get "fresh
sectors" all the time, UNLESS the error is not correctable. If it isn't,
it will be written "as is". Further, some CD-Roms like to deliver
garbage in the ECC in certain situations. I hope you got the point.

Regarding SD2: Maybe it "might" work better now. If it does, good for
you. The change wasn't made with SD2 in mind. The "regeneration"
change gives an overall enhancement of the copy, so it "might"
improve the ability of CloneCD to copy a certain title on certain
equipment. There is no "in-built" BetaBlocker or anything similar.
If there was, I wouldn't be able to sell CloneCD in certain countries
like the USA."

He does have a point there, if you would try to sell software with a
build-in BetaBlocker function it is very likely you would not be able
to sell it in the United States, because of their pretty strict laws
when it comes to digital technologies.