I guess what I was getting at is that in my little world, none of those looks would fly. I can dress up denim, too, and I don't like being told not to wear it, esp. when in my mind there's a big difference between dark jeans that have no holes or distressing and are styled like dress pants and the ripped, distressed, washed out jeans being featured now.
Last week our office hosted an ag event that included farm tours and a lunch. Yes, I showed up in jeans, as this was an outdoor event. I wore a sleeveless NYDJ top, dark wash denim legging-style jeans with zippers at the ankles, and Dansko platform cutout booties. I received lots of compliments, esp. on the shoes, yet was still comfortable in that midday heat & humidity (it rained later that afternoon), So even for an event this casual, I was presentable, as was everyone else. It was open to the public, and there were tons of people there.
For most events, however, jeans are not worn. The older ones like my DH are the ones who work to get grants, etc. and they are the ones who always dress nicely - no matter what. My DH doesn't even own a pair of jeans.
That said, I do like the book. There's still helpful information in there.