Matt Waldman’s RSP NFL Lens profiles Darren Waller’s 2018 stretch-run with the Raiders and what it reveals about Oakland’s potential use of him in 2019.  A former big-play, split-end at Georgia Tech, Darren Waller has always been an impressive physical specimen. A 6’6″, 238-pound option, Waller had impressive pre-draft marks: a 37-inch Vertical Jump, a…