i have never seen them being used, or used them in my own baking from shortcrust, sweet paste, puff and breadmaking. So perhaps i cannot speak to their advantages, however i have found ways to achieve any and all of the things they claim to provide
using a Rational oven renders them further obsolete
Imho perforations have never made a difference in the outcome of my tart crusts. Do a search on my user name for threads involving tart crusts. You'll learn something. (EDIT) Blind baking is followed by filling the baked dough and it's then bake some more.