Understand what wedge grooves actually do
The instructor explains that the milling between a wedge's grooves is not primarily what produces friction and spin. Using a tire analogy, he notes a racing slick (full surface, no grooves) gives the most traction in dry, warm conditions; grooves exist to extract moisture or debris when the surface is wet or dirty. So people tend to expect a milled specialty wedge to spin far more than it actually does on clean contact.
Channel: Club Champion
Watch official source at 7:27