If another big mining pool goes down we may be looking at 40 mins between blocks maybe even longer - transactions are not processed if no blocks are solved.
Statistically, even if hashing is at the target rate then once every 48 hours there will be at least one block that took an hour to solve. Can you remember even one time that this was a significant problem for you?
And if one pool suffers technical issues those miners will just switch to another pool.
As far as this being a problem if hashing capacity drops below target and that persists for a couple weeks ... there is little difference between six confirmations taking an hour versus six confirmations taking two hours.
With most of the costs for ASIC mining being fixed (i.e., for the purchase of the equipment), there is little reason why hashing capacity would suddenly drop dramatically.