[casualwriter]

yes, I do testing on production usually. I feel much comfortable if can perform enough testing in production, before inform end-user to start use it.

In my experience, it starts from DESIGN PHARSE, which should be awared to make it possible to test in production without impact end-user. CODING PHARSE shall make some arrangement to provide more possibility for testing on prodcution environment. DEPLOYMENT process shall be able to provide a time-gap like "pre-launch". Then will be happy to test in the "pre-launch" period in production, and feel confidence to infrom end-user for a release.