I'm going to channel my inner John Morgan for just a moment - common fans really suck sometimes.
First of all, Walter Thurmond HAS played an entire season for us. 2010. He participated in 14 games. He didn't start, but he was definitely one of the "defensive interns" Pete was developing, along with Kam Chancellor.
Second, I just recoil when physically healthy fans fold their arms, stick their noses in the air, and snidely proclaim what another person's physical problem is. What's the biggest risk YOU take for the Seahawks, getting punched in the stands by some drunk guy in the row below you? Of course it isn't our job to stay healthy, it's the players' job, but the grueling nature of football should induce some understanding from us. That perspective seems lacking sometimes. This is a guy's dream, he's worked hard to overcome it, and luck just hasn't been on his side. Yet we consider it our...birthright? as fans to bash a person when he isn't fully able to perform for us, as if our status as consumers shields us from having to include any other consideration, or gives us the right to vent our frustration by promoting the end of a person's career. It's all about us, like he's offended us somehow.
Third, Walter Thurmond is not draining this team by being unable to stay healthy. As someone else pointed out earlier, there are a myriad of players who have been languishing on the roster and taking up space without actually being a hindrance to anyone. I haven't heard anyone complaining about Jaye Howard's perpetual foot injury and demanding he be cut. Thurmond simply gets this treatment because he's more high-profile and thus higher on the "fan frustration scale", not because of some rock-solid philosophy where every individual on the 53-man roster should be ready to contribute at a moment's notice. No roster in the NFL is like that all the time.
Lastly, give the player some credit for his skill. PC has stuck with this guy through thick and thin, and that says something about his ability as a cornerback - the exact same thing that his play does. He's good. He's not being IR'ed because he's "unable to stay healthy" or some such ridiculous artifice on the level of judging a team's mental fortitude by studying four-second camera shots of the sideline bench. Nor should he be benched for that reason, not with his talent. He's being IR'ed because he might have genuine competition at the position of slot corner, and THAT makes him more replaceable. That's a good reason to put him aside. Until then, whom did you plan on replacing Thurmond? DeSean Shead?
A player struggles with his lifelong dream because of an uncooperative, agonizing leg and WE feel all inconvenienced as fans. Someone tried to defend this position by saying "I'd want Steve Largent gone if he struggled this much too", but he failed to mention how he'd feel if Largent got healthy immediately afterwards and went on to catch 100 touchdowns for a more patient team. If you think that sounds silly, think of Russell Okung.
/sermon