Actually they get more accurate later in the game. Early on there is too much fodder.
I completely disagree. With a larger pool if there is one stand out it is overwhelming. When the pool gets smaller the averages are too close to measure accurately with the Dial Idol method of busy signals.
Not sure but if I were to guess Dial Idol has a larger measure. Never heard heard of Vote Fair before you pointed it out. Has it been around long? Dial Idol has been doing this for a while and also does DWTS and SYTYCD too. Then you have Vote For The Worst to contend with. All I know is Dial Idol had Bristol spot on every week last year and failed with Idol when it came down to 4 people.