Free agency? The 49ers didn’t exactly tear it up. Maybe it was the right thing not to do — tear it up, that is.

They signed three players. Nose tackle Ian Williams and kicker Phil Dawson, who were their own guys. And Thad Lewis, a third-string quarterback who played for new 49ers coach Chip Kelly in Philly. Lewis knows Kelly’s system, which makes him valuable to the Niners because just about no one else knows Kelly’s system. Call Lewis a “camp arm.” He will last through most of training camp and almost certainly go the way of all camp arms with a ticket to nowhere.

According to what I’ve read, 49ers general manager Trent Baalke tried and missed on the following free agents. Cornerback Sean Smith signed with the Raiders instead of the 49ers. What a revolting development for Baalke, and it means the Raiders are resurgent while the Niners are merely regurgent. Cornerback Casey Hayward signed with the Chargers instead of the Niners. The Chargers? Good grief. Running back Doug Martin re-signed with Tampa Bay instead of signing with the Niners. But maybe a re-sign doesn’t count as a 49ers flop.

Why didn’t Baalke tear it up in free agency?

Complicated question with multiple answers. You know, it’s one of those “all of the above” answers. Here are some of the aboves. 1) The 49ers are dreadful and will be dreadful and there’s no good reason to sign high-priced players who won’t make a difference right now. 2) The front office has a bad reputation around the league, a reputation it worked hard to earn. 3) Chip Kelly has an absolutely toxic reputation among players.

For the sake of concision, let’s focus on Door No. 3, the Kelly Toxicity Door. Not to say Doors No. 1 and No. 2 don’t matter.

What’s the deal with Chip?

He worked overtime to alienate big stars when he coached the Eagles. You know the back story with DeSean Jackson and LeSean McCoy, how he turned them off, how they told the world about it. Word gets around fast. Players from different teams share agents. Players work out together. Players are friends. You can bet some players say avoid Chip Kelly at all costs.

Well, what’s so bad about Chip — if there is anything bad about him?

He is controlling to the max. Treats his players like babies. Urine tests daily. Tells grown men when to sleep. How to live their lives and be a professional. As if they don’t know. As if Chip knows.

Hey, Chip, be sure and tell NaVorro Bowman how to be a pro and when to nap.

Playing defense for Chip is brutal. Could be why Sean Smith signed with Oakland, among other things. You know the deal with Kelly’s defense. Spends lots of time on the field. Defends more plays than the average defense. Almost lives on the field — might as well set up tents.

Players in a Kelly defense get bad stats. Their value goes down for their next contract. Not a good thing in the short violent life of football players.

While we’re piling on, here’s another black mark against Kelly. Colin Kaepernick doesn’t want to play for him. Won’t give Kelly a chance.

Grant Cohn’s Inside the 49ers blog