Infant mortality and longevity of DVD media?

First, I don't think that DVD media is subject to "infant mortality" at all, which is not to say that a just burned disc can't be defective. Now a couple of things that look like infant mortality are possible, although the mechanisms are not the same as what we usually call infant mortality. One of these is that data written a burner whose laser power is below spec can "fade" over time, but this is mostly a problem when using "RW" media (which should be avoided for archival and backup uses). Also, a media that is subject to bending can delaminate .... DVDs are a sandwich of two layers of plastic glued together, and the data is stored on a dye layer coating on the inside, at the juncture of the two layers. Delamination is fatal to the data, and normally occurs from the outside in .... Good advice is to only use 80% to 90% of the media capacity, leaving the outside edge (which is where the first damage usually occurs) unused for data anyway. Second, there is no doubt, I don't think, that dual layer media is considerably less reliable than single layer media (knowing how dual layer works, it's hard to believe that it works at all). That said, I have not yet had a problem with any of the dual layer backups that I've made. The subject of optical media longevity is one of considerable debate. All studies by the media makers suggest a life of several decades to centuries, but some skeptics insist on saying less than 10 years. I have optical CD media that is now 12 years old that I can still read just fine. I think that some of your practices are excessively conservative (such as only applying power when the drives are being used), but will do no harm. The biggest risk, I think, is burning with a marginal burner (low laser power and/or bad or just dirty optics). Reading the media with a variety of drives other than the one used for burning is certainly not a bad idea, but for most users is unacceptably time consuming.