Could it be you're just arguing for arguments sake?
My original point was: A RAID0 over 3 disks is about 3 times more likely to fail than a single disk running standalone. Fail means "total data loss". You confirm that point with your own math, yet still seem to be trying to argue that there was no difference. Sorry, that makes no sense to me.
"A RAID0 over three disks has about 1/3 the MTBF of a single disk."
This is incorrect, the MTTF and MTBF are not significantly changed. Assuming you meant failure probability, my issue with the probability variance is the linear relationship you imply.
If the variation were linear, a RAID array composed of drives with a 5% failure probability would reach certainty of failure (1.00 probability) within the interval at 20 drives. In actuality, it takes 225 drives to reach that probability.
The difference is a real world consideration for capacity management. What it means is that RAID0 arrays are not as failure prone as people think they are.
The person that wrote the Wikipedia article you referenced read the same mythology you did; repeating it doesn't make it true. The plural of anecdote is not fact.
Think about it yourself for a moment. If two cars are traveling 50mph, does that make their average speed 25mph (50/2)? Applying a divisor to a failure rate based on the number of devices is nonsensical.
You're right, there's no reason to try to correct the 20% of the population that believes the Sun revolves around the Earth. It's a lost cause; you win.
You're right, there's no reason to try to correct the 20% of the population
Erm wait, didn't I just suggest the exact opposite?
If you really think everyone has been wrong about this all the time then please, by
all means, correct wikipedia or write a blog post about the matter.
This "false" formula has been out there for quite some time and you find it
in pretty much every write-up on the topic, including those from RAID-vendors
who (I'd hope) have spent some thought on these things.
On the flip-side I haven't found a single source to support your thesis.
Thus I'd say the burden of proof is on you.
