I like your reply, it has merit, but it relies on certain assumptions that might not be correct for the majority of drives out there.
Certainly the Plextor and Toshiba drives return a read error if (a) twinsector(s) are found.
I presume that they do this because they don't know which sector to return - even though they are identical. I guess it must be something to do with the read-ahead logic?
(Someone correct me if I'm wrong?)
Certainly the Liteon drives "ignore" the twinsector.
An interesting or perhaps useful side-effect of the disc images created during the early Twinpeaks days, was that if you put too many twinsectors on a disc, the Liteon drives could no longer read the ATIP of the media. Now this might be useful in the future.
Try it for yourselves, next time you back up a SecuROM disc, using Twinpeaks 0.2, select a higher value for the number of twins to insert.