oddsod - 5:20 pm on Aug 2, 2005 (gmt 0) RAID is not a substitute for good backing up procedure and practise.
There are several reasons why RAID is not a good idea if you're not a typical transistor head. This article [bestpricecomputers.co.uk] covers the point you make about the second drive being a backup of the first, warts and all. There are some tips on protecting yourself if you are currently using RAID... but the tips are not much use if you've already run into problems.
RAID is not a substitute for good backing up procedure and practise.