I've been reading in a couple PUA texts flaking on plans (occasionally) with a girl can intensify attraction (DHV- you have other shit you are doing in life) , and to reduce the appearance of neediness.

What do you guys think about this? Does it accomplish the goal of reducing the appearance of neediness and little DHV? Is it worth it? Is it rude and a complete waste of time? Is it necessary in all cases? Some? Never?