If a player's contract goes to arbitration, the team has to somehow concoct an argument that said player is NOT worth the money he is asking for. Using another player as a comp is not uncommon. There is really no way to do ti without creating an argument that the player is going to like and agree with. This type of argument the Sox created is inherent in the process, but the Boston press makes it sound like they were the first team ever to do such a thing.
Like every other player to come to arbitration was met with "We say you're only worth $X", and then replied with "OK, you got me."