This article doesn't make them out to be great.
The book that is mentioned in the article "Getting them to give a ****" said pretty much the same thing as the article just stretched to 250pgs.
Personally I think that both the article and the book completely missed the boat.
In my experience the quality of employee has nothing to do with age. It is more based on the system they work under.
Did you hire well, are you training well, do you explain there job (actual job description), do you give opportunity to advance, do you give opportunity to learn, do you treat them with respect, do you show them you care about them, shoot, do you even listen to them?
If one day no managers showed to work, aside from maybe getting cash out of the safe, the restaurant would be able to continue running, if no hourly employees show up to work nothing happens. That is how important my staff is to me.
I personally believe that if you strive to make your restaurant the best place in town to work you end up with a hard working & loyal staff, regardless of age, and a profitable restaurant.
I have been called crazy before, and they're right.