That´s 100% correct. They just do whatever THEY feel is right. Instead there are rules to follow. I remember this shitehouse de Jong not even getting a yellow for breaking the leg of this Newcastle midfielder a couple of month ago. It became a joke really...
Its a no win situation though. And one which the refs use to their advantadge whenever they feel like.
Half of the supporters/pundits continuously call for the refs to use common sense to apply the rules. The other half say the rules are there to be obeyed.
Refs are in the position now where they can decide which side of the fence best suits any controversial actions. The Gerrard/rafael situation is a perfect example of that IMO.
Gerrard was sent off because he left the ground and lunged in, with contact on the player. Rafael left the ground, lunged in, and if Meireles hadn't pulled out (sensibly IMO) he would have ended up with a broken leg. The actual offense occurred, although due to a player having the foresight to not get his leg broken there was no contact. Webb let it go because of that. However, IMO, if he was reffing by the letter of the law he should have sent Rafael off. Same offence, that allowed advantadge to the player comitting it, which then led to Gerrard losing his head.