Just look at someplace like USC. Been a dumpster fire, like us, for years. In 2018, they were 78th in scoring offense, 58th in YPP, 65th in passer rating, 59th in YPA.
They bring in Graham Harrell, and in YEAR ONE, 26th in scoring offense, 15th in YPP, 13th in passer rating, 15th in YPA. Oh...