During Patterson's first two seasons (2013-14), Minny tried using him as a "deep threat", at least some of the time. His average YPC was 11 yds (54% YAC), and his catch rate was a mediocre 54%.
Then, in 2015, the Vikes used him almost exclusively as a KR (only 4 total touches in scrimmage play).
During his last season in Minny (2016), and then last year in Oakland, Patterson wasn't used as a "deep threat" much at all. His average YPC was still about 9 yds, but with 69% YAC (< 3 "air yards" per reception). His catch rate jumped from 54% to 69% with that change.
Another aspect of Patterson's overall game to consider is that he averaged about 10 rushes per season for 110 yards, on jet-sweeps, end-arounds, etc. That's something that Edelman has typically done that Patterson may now cover.
Anyway, the debates surrounding Patterson's route-running, and about whether or not he can be a "deep threat", seem kind of tangential to me. I'm really not certain why folks are even thinking in those terms. It feels like building arbitrary expectations that are almost certain to go unfulfilled - thus "proving" the summary dismissals that "Patterson sucks as a WR" and is "only good for gadget plays".
Sure, he has speed and he carries the nominal positional designation "WR", but f**k that. Why not evaluate him for the role he can play? His optimal role in the passing attack seems to be closer to that of a receiving RB or a move TE. Thinking of Patterson as "AHern-lite" makes a metric crap-tonne more sense to me than comparing him to Moss and other, true WR "deep threats".