Matt Waldman’s RSP Boiler Room examines the technique of 2018 NFL Draft prospects, WR Calvin Ridley of Alabama. Many football fans and analysts underestimated Rams wide receiver Cooper Kupp. It’s easy to do when the likes of Cris Collinsworth broaches Kupp’s 4.6-second, 40-time on weekly basis to a national audience. Kupp’s slow time is a…