Erhardt-Perkins is a modified WCO with deep ball concepts taken from the Coryell philosophy. If you research the Erhardt-Perkins system you'll find that the two systems came together with one coach from each system working together, I believe with the Parcell's Giants. And yes they made a bad hire last year and tried to make their running, deep ball QB, a pure WCO QB and if failed at which point they changed and allowed for deep balls and QB running, but the OC was not schooled in either.