I have seen this happen many many times and have at times tried to stop and fish the "hot spot" with mixed results. In most of the cases the bite wasn't happening compared to the long line bite. I think its has to do with the jig depth/speed that makes those fish holding in those spots bite and in most of the cases for me there wasn't a brush pile or something to target that the fish were relating to. Will be interesting to see what others have found in these situations.