How is it ducking someone ranked way below you?
What do you have to gain by fighting someone ranked lower than you if you are trying to move up yourself.
Unless you are the champ, or have a chance for a big money fight, it is foolish to fight a lower ranked opponent. You should be focused on moving up in the ranks or padding your bank account.
Low ranked guys want to leap-frog to the top, and if people aren't interested in allowing them to try this, they are "ducking".
This is nonsense.
When Bisping fought Dan the second time, you can say he ducked more legit contenders. He claimed a personal vendetta, and he had the pull to fight Dan, so more power to him.
When he fought GSP, I say fair play. He made a pile of dollars off that one.