I'm looking a lvling method for levels 1-90. Is boosting RaF'ed accounts with a lvl 100 faster than the two RaF'ed guys doing LFG?
I haven't used a high lvl to mass kill for lvling someone else in a long time. When I did it the experience per hour was much lower than questing or dungeoning. It was the slowest method of all, but was faster than lvling a character solo without RAF.
I wouldn't advise the use of the lvl 100 for two reasons. First, I vaguely remember Blizzard implemented something to nerf this method. Second and the biggest reason, it involves you setting up in a small area and killing for long periods of time. You won't be able to move the low lvl characters around in the zone that you will be killing in, so you will need to put them somewhere out of harms way. You also have to kill a lot of mobs for this method, and there are very few places that will meet the criteria. It is one of the riskier ways of lvling.
Prior to this expansion the method I used to lvl RAF toons was dungeonbuddy. I don't recommend doing it AFK, and even if you are going to be monitoring I don't recommend that you use anything other than DPS. People expect tanks to mass pull in low level dungeons. The bots are not going to do a good job of that. People will get impatient and mad at how slow you are. If they are mad at you and suspect you are a bot then they will report you. If you are a healer then the group will likely wipe a lot because they will take shortcuts and mass pull while you take the long way round. Even if you are just DPS it is extremely risk to AFK using dungeonbuddy.
The method I currently use to level characters together is partybot. I play one account and run HonorBuddy with PartyBot on the second account. It follows me around and assists me. I have to manually pull and turn in quests, but it's not that big of a deal.
The best AFK method if using the lvl 100, but I would scout the location first to find out how popular it is. The fastest method by far is DungeonBuddy. I would recommend that you use DungeonBuddy and don't do it afk. You can get them leveled up in a day or two. If you use the lvl 100 it will likely take quite a while, and the longer you do it the more at risk the accounts will be.