If the oil in your cannister is 100% clear with no residue in it, then it was a waste of time to install. The problem is not the engine, it's the environment. With slits in the valve cover, the first thing to get plugged up due to excessive muck is the hollow rocker assembly tube. No oil to the top end is the result. If the filter staves that eventuality off a while, it is worth having. This is a common reason for engine failure on these engines.
That coupled with no PCV below 30mph and the crankcase gasses are mixing with the oil causing damage and adding even more muck into the system. It was a poor design but part of the evolution process GM went through and since these are our target engines and the love of our lives, we do not think of them that way.
The only reason I do not disagree with the above posts is because a really dirty oil filter system can be the worst possible scenario being a Dirt Dispenser, a gift that keeps on giving if you do not change out the filter and clean the canister at timely intervals. Also, the idea of filtering 12% of the oil, with no guarantee all of the oil will ever be sent through the bypass IS to my way of thinking an option as opposed to a necessity.
Thankfully, the next generation went to full flow filtering and PCV. The upper assembly will be clear forever as a result. It's all about the evolution process. You can see a similar path if you study Ford or anyone else.
