I think it's quite possible that Dana told Rashad to say this, to see what the reactions from the online community would be and to stir up interest in the fight.
I don't see any point in calling out the champ from the division below you unless you are going to go to him or are already a champ.
I like what Cormier is doing with Bones, but to say you can definitely beat someone but won't go to their weight to do it is pretty retarded IMO.
Actually after re-reading, Evans didn't say that he wasn't going down to 185 lbs. All he said was that he wanted to do a practice cut to 185 lbs first to see if he could even make the weight, and that he wanted to fight the best whether it be Bones Jones or Anderson Silva. The closest he came to saying that he wasn't going down was that "it would be bittersweet because he knows he'd win". So it's not like he's ruling out the possibility all together.