GSP fought BJ when he was ranked 3rd, Anderson refused to fight Machida after BJ lost and Machida was 3rd. Anderson didn't fight Rashad who has always been on the list. The UFC made Jake Shields who was a MW on the p4p list drop down to WW to face GSP.
I don't get how the guy who has fought two guys on the p4p list (Penn, Fitch) and is taking on a third (Shields) is a coward over a guy who hasn't faced any 205ers on the list.
Jake Shields is on the P4P list because he is a WW who had a win streak in that weight class who moved up to MW and won some fights and a title. BJ was on the P4P list because he was a LW who moved up to WW and won the title. GSP fought a smaller guy moving up in a super fight. Now that he doesn't have the advantage of being the naturally bigger guy in the super fight he waffles and wants a catchweight.
Andy won't fight Machida because they are close friends and stablemates and I don't remember Rashad ever being offered to him. The UFC doesn't want to use Andy at 205 unless he is staying there because him wrecking contenders would **** up the division. Which is why Dana wants GSP to move up to 185, challenge for the belt, and stay there. The UFC doesn't have a super fight model they want guys to pick a division. Andy is really the only guy who has bounced to another weight class won and not stayed there that I can remember.