This play actually does a nice job of illustrating my point. Mariota and Oregon's offense give you very limited chances to see NFL style throws, reads, and progressions. Here is a play that gives you a NFL style route concept with a NFL style read:
View: http://espn.go.com/video/clip?id=espn:12108741
This is the 4th down play. You have 3 WRs bunched with the outside WR running a spot route, the middle WR running a corner route, and the inner most WR running a flat route. This play is similar to one many NFL teams use.
Anyways, most of the time, the WR running the corner route is simply a decoy unless there's a coverage bust. His job is to clear out the coverage and to make the QB's read easier. The QB is reading the flat-spot combo. In man to man, the spot route usually will pick the CB playing the flat. If the flat route is successfully covered, that almost always means that spot route is open. You just have to recognize it and throw it quickly before the window closes. This is true on this play. The safety crashes down and takes the flat WR while the CB does not pick up the spot route. Mariota should have spotted this and known that the spot route is open. He doesn't. And they don't convert.
Now, I'm not saying that Winston is perfect. I'm not saying he doesn't miss reads or throws. But Winston gives you a lot of opportunities to see NFL style concepts, route combinations, and reads. Mariota does not. He has to make them count.