My problem with all the writing about Joe Mauer moving to first base, specifically regarding the concussion issue being the catalyst for the move, is that there are multiple factors going on right now.
The first is that, after losing Justin Morneau and his power, the Twins are even more cautious than they would have been two years ago. With as much money as the organization has tied up in Mauer, it only makes sense to remove him to make sure he doesn't come back too early (as he's often tried to do with other injuries). The move to pull him is precautionary, not reactionary. They didn't let him come back because they don't want to make things worse, not because they are already bad.
The second is that his wife just gave birth. We don't know how that's affecting his home life, sleep patterns, or anything else. As any parent knows, the first six months tend to be the hardest because kids don't sleep through the night, and they constantly need feeding/changing/checking on to make sure they don't get too sick or go through SIDS. Joe wants to be on the field, but he may just not be able to adjust between the concussion symptoms and the children. It's going to be a factor, just based on the reality of sleep being a factor in health.
The third is that I have seen far more players become injured as a result of aggressive base-running and defensive gaffs in the outfield than we have catchers from being knocked by bats and balls to the mask. Now, that may be because those types of plays are more visually spectacular or disturbing than the routine clipping of the bat into the mask or the 95mph fastball right on the steel/titanium cage. I tried looking for some statistics, but my search phrases didn't pull up anything to back up either side.
In short, saying "Mauer should move to first" is lazy journalism. It's speculative based upon a lack of knowledge. There's no proof that Mauer would be any safer at first than behind home plate. Morneau certainly wasn't safer because his injury occurred on the base paths. Manny Machado wasn't safer, Alexi Casilla wasn't safer.
We're not talking about Mauer's knees or legs or anything else that goes through wear and tear harder behind the plate than any other position. At least that is a valid argument. Concussions are happening ALL OVER the field. At least behind the plate, Mauer has protection. The new titanium cage helmet is slightly lighter than the steel cage one, but apparently has issues dissipating the force of the impact.
What writers SHOULD do is talk about why Mauer should continue staying behind the plate and how to make his tenure last longer. Should he go back to the steel cage mask? Should he take up the hockey-style mask? Is there another option that nobody has thought of?