"and doni's going to say, ' the integrity test was a verification between the onboard memory and secondary storage, ie SD,"

No he wouldn't, doni's focus is not on the initial integrity test(scanning for bad memory issues), what doni cares about is what happens after the integrity test in tracking the bad memory segments containing bad memory cells....and keeping them in check with data stored..

doni has mentioned this may times as well....

doni