Not sure how well this works out in practice, but if one drive returns a read error for a sector and the other returns the corresponding sector without an error

Not sure how well this works out in practice, but if one drive returns a read error for a sector and the other returns the corresponding sector without an error, it should be a simple matter to trust the latter. Of course that assumes that storage corruption occurred after uncorrupted data was written to disk. Modern drives have rather large per physical sector checksums to detect the occurrence of these errors and presumably retry a couple times before returning an I/O error if configured correctly. In addition a good I/O bus should have error detection checksums for data in transit, and good hardware should have ECC RAM as well.