I have a feeling that a lot of the "venom" you discuss stems from TD's treatment of the fans, as opposed to his failure as a GM. I also agreed with a lot of his moves, (although NOT trading up to get JP [or even taking Evans earlier that round,]) but hopefully he's still held to a higher standard in football operations than I am.
The thing that gets me is the arrogance and contempt. Not just for the bandwagon fan, but also for the diehard, the dillusionist, the media -- and basically, the whole damn community. Bad things DO happen. People tend to be more understanding and forgiving, however, when the person making the mistakes isn't a complete jackass.