Final Regular Season QB rankings

[Shake n Blake]

http://www.footballoutsiders.com/stats/qb

Dalton ranked 13th (out of 34 qualifiers) in Pro Football Outsiders DVOA which is a system that rates QB value.

He finished just behind Andrew Luck and ahead of the following QBs that bfine and others would take over Andy:

Russell Wilson
Jameis Winston
Marcus Mariota
Phillip Rivers
Cam Newton
Alex Smith
Carson Palmer
Eli Manning
Joe Flacco
Ryan Tannehill

Now if Dalton is "mid-tier" (again...A very broad and vague term), what are these guys that graded below him?

Of course, only PFF and bfine agree with OP are reasonable, so I'm sure we can dismiss PFO.