A well fed crappie is a finicky lazy crappie. I deal with this at Lake Fork, Ray Roberts and Possum Kingdom and any lake with lots of bait fish.
A good analogy is after you are in your recliner full of turkey and all the trimmings and your wife tells you the pumpkin pie is ready. Now you might not get up to get a piece since you are practically in a coma, but if she would bring you a slice with nice whipped cream on top you would take it.
This is how those crappie are. They are full, as they live in a lake overflowing with shad. But if a dead or dying minnow would find itself right in front of them, they will take it. I can tell when this is the case with lively minnows. If I bring a minnow up and he's wrapped the line around and around the weight, it's because lazy crappie have come over to take a look. A dead or dying minnow usually gets a bite when this is going on.
John 21:3 Simon Peter saith unto them, I go a fishing. They say unto him, We also go with thee.