I totally agree with the article, and all subsequent comments.
I'd like some debate, however, so I'd like to state 2 extremes, and ask where people's tradeoffs are?
1. Critical system, 24 hour access, any downtime at all is damaging.
2. Non-critical system, used every Friday for 5 minutes, doesn't matter if it doesn't work for a month or so.
I'd be surprised if there is anyone who would make changes to a live 1, and I'd also be surprised if there is anyone who would NOT make changes to a live 2.
There must therefore be a middle-ground somewhere. Ultimately this middle-ground should be decided based on cost and business risk, but I would be interested to know where YOUR middle-ground is...
Solutions are easy. Understanding the problem, now, that's the hard part.