They are covering all the bases that others might implement...

As well as what they do them selves.

Theres a reason for this...

3.At step 530, representations of error location and types are used to create a reference map which uniquely identifies the semiconducting device which was written. Alternatively, the reference fingerprint may comprise a linear feedback shift register to compact the error locations rather than storing the numerical representations of locations and types of error obtained in step 520.

There is no overhead to the Alternative method(data mapping).... Also, with the alternative method(as 445 is able to do)...data segments(files, or representations, whatever you might want to call them) can be individually secured as well.

doni