Why don't we extract _every_ AP25 response from the original disc then patch our games with this data so that our backups will never need to be re-burned?
Not feasible. The console is currently sending 13 challenges to the drive to produce response data that can be captured. Microsoft could change the challenges at any time at which point we can capture the new response data. The total number of possible challenges is potentially very large as each challenge includes two disc locations and there is a lot of suitable locations on a disc.
Ok so if I understand this correctly, there is an unlimited number of AP2.5 challenges? Is the AP2.5 data not stored on the original disc? The original discs cannot be updated in any way so why can't we copy all AP2.5 data from the disc? Or is it that it is only possible to extract the AP2.5 data needed once the challenges from the updates are known? The way I see it; once the challenges are known from the updates, you can extract this data from the disc, because you know what data to extract. Is this correct?