In a word, brutal. He did lead the team in tackles with 104 and also led in solo tackles with 61. The numbers seem like an exceptional season, but he also missed a ton of tackles. He also struggled in communication with fellow safety Ryan Murphy and that resulted in several big plays being given up. They are not always entirely his fault, but he needs to help figure it out as well.
The mistakes were plentiful, but he was given too many plays to make as well. The Oregon State defensive front was so full of holes he had to be overly aggressive, which may have effected his mindset as well. He did help make plays and was an effective stop gap, but he also took poor angles and communicated poorly, counteracting many of his positive effects.
It was hard to get past all the mistakes, but Zimmerman has a ton of potential to help make the Beavers better this season. He has all the ability required to play the strong safety position. His skill set includes quickness, strength, and speed, and they are all good for his position. What he lacks is just fundamentals, which is what makes it all the more frustating.
His Oregon State career started at wide receiver, but before his first camp ended he moved himself to safety with a glut of receivers in front of him. This should be referenced as it may explain some of his poor tackling, although the Beavers as a whole do not tackle well either. This is both the curse and blessing of Zimmerman, he has not been an overachiever so he has the potential to turn it around in a year. He did not struggle in communication in his first year starting, although Jordan Poyer may also have had something to do with that.
Zimmerman has the ceiling to help make the Beavers secondary great though. Ryan Murphy is a good safety, Steven Nelson has been good at cornerback, and I believe in Larry Scott/Dashon Hunt. If Zimmerman can eliminate mental mistakes he will have a fantastic year. The physical side is all there, he just needs to play fundamentally sound football to make his senior year a great one.