This could've gone as a fun fact, but I wanted some headline variety.
Following that puzzling midseason trade, Russell Branyan appeared in 57 games with the , batting .215/.319/.483 and in no way making them more watchable. Over those 57 games, the M's scored 171 runs, for an average of 3.0 per game.
In the Mariners' 105 games without Russell Branyan, they scored 342 runs, for an average of 3.3 per game.
In the Mariners' 31 games without Russell Branyan after he was already acquired (note: he missed a lot of games), they scored 87 runs, for an average of 2.8 per game. Many of those games were over the final two weeks, when the M's were fielding most of Tacoma's regular lineup.
One of the explanations for the Russell Branyan trade at the time was that having his presence in the middle of the order would allow the other hitters to loosen up, having had some of the pressure on their shoulders relieved. What we find is that, if they felt looser, they weren't playing like it. Overall, the Mariners' offense was actually worse with Branyan than without him, and if you limit the window strictly to those games played after the trade went down, you see only a tiny improvement - presumably because of Branyan's .802 OPS, and not the effect Branyan's .802 OPS had on others.
This post isn't intended to argue that protection theory is wrong. I think it does make some sense, even if it's difficult to investigate. It's easy to believe that, as the Mariners continued to sink lower and lower, the hitters started putting too much pressure on themselves to make something happen. Pressure they might not have felt were there a productive slugger in the middle.
Rather, this post is intended simply to show that, even if a lack of protection was the lineup's biggest problem in 2010, Russell Branyan wasn't the answer. Russell Branyan wasn't even close to being the answer.