Okay, well I guess that’s a bad experience. I don’t think it invalidates the fact the usually book authors should be somewhat knowledgable - of course it doesn’t automatically
mean that all of them is good to work with.
I mean it's in general like if you hire a PhD into a role that needs to cover a lot of areas, can't be super detailed in anything, and needs to get stuff done as opposed to pure research.. that can turn out poorly.