Peter,
Can I make a serious attempt to sum up your argument as:
Disks suffer from random *detectable* corruption events on (or after) write (eg media or transient cache being hit by a cosmic ray, cpu fluctuations during write, e/m or thermal variations).
Disks suffer from random *undetectable* corruption events on (or after) write (eg media or transient cache being hit by a cosmic ray, cpu fluctuations during write, e/m or thermal variations)
Raid disks have more 'corruption-susceptible' data capacity per useable data capacity and so the probability of a corruption event is higher. Since a detectable error is detected it can be retried and dealt with.
This leaves the fact that essentially, raid disks are less reliable than non-raid disks wrt undetectable corruption events.
However, we need to carry out risk analysis to decide if the increase in susceptibility to certain kinds of corruption (cosmic rays) is acceptable given the reduction in susceptibility to other kinds (bearing or head failure).
David
tentative definitions: detectable = noticed by normal OS I/O. ie CRC sector failure etc undetectable = noticed by special analysis (fsck, md5sum verification etc)
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