The problem with those stats is that it only includes the catches. Don't have any source for where the attempts were made yardage wise, but my perception last year was that a bunch of attempts were made to Bradford 20+ yards down field (and some to AJ as well) and those were a serious source of non-receptions.
As for the dropped pass statistics--I originally got those from Stats, Inc. Here is what they say about it:
Any incomplete pass which was catchable with normal effort. STATS compares and reviews the judgement of multiple reporters to determine if a pass was dropped.
Obviously that there is a lot of subjectivity to what is "catchable with normal effort" but my original purpose in looking at it was as a comparison of WR's across the league--so long as the standard is applied evenly then whatever it is still gives a good indication of whether a WR has a problem vs. other WR's. IMO, in order for Bradford to play a larger part in the offense (a) they need to attempt to throw it to him more in the 10-20 yards down range area and let him make YAC (Miami game classic example) and (b) the QB's need to be more accurate when they go 20+ yards to him. It was just sickening on more than one occasion last year watching him with 3 steps on the db and no deep assistance (i.e. basically a sure fire TD) and then get overthrown.