Jerry's had success trading for "future" picks (high picks) that's how he (Jimmy) built the great 90's teams but he hasn't had success trading down and selecting players during current drafts. Hard to find corner stones in the 5th, 6th and 7th rounds. The Cowboys used at least one pick they got from Cleveland to move back into the first round to select Spencer. They traded a 2nd, 3rd and 5th to Philly to make that trade. The point is Jerry traded "up" for Spencer not down.
If you're trading back and picking up a teams #1 the following year that usually works out pretty good for most teams even Jerry's had success with those. It's these trade downs that are only amounting to 5th, 6th and 7th round picks in the current draft that are blowing up in Jerry's face.
I've lost track of how many trade downs Jerry has made that helped him accumulate a bunch of 6th and 7th round draft picks. The odds on striking gold or even silver aren't real high in those rounds. Once you get to the 4th round the draft becomes a real crapshoot you're throwing darts at that point.