Deng isn't happening, people need to accept that fact.
1) Deng is Chicago's top priority, they have a glut of guards, but only really have Deng or Nocioni as starting forwards, and Nocioni is a stretch.
2) If you make the deal for Deng, then Pierce becomes this teams' spot up shooter because Deng doesn't have a good enough outside game. Problem is, Deng doesn't have the midrange game that Pierce has either, so an offense that wasn't spectacular to begin with is further hampered. We're better off taking Gordon, who has lower value but is a better fit, and getting another productive player. We would be worse off in a Deng/Allen swap because Luol and Pierce don't mesh well.
3) Chicago wouldn't consider Deng for Allen because they're rebuilding, and Deng is a significant piece of the equation.