I'm willing to bet that the Saturn and other late model GM canister type filters are not operating any differently than any other oil filter on any other OEM engine set-up. I doubt it's a bypass type filter (I only say 'I doubt it' because I don't have a oil flow diagram for these engines in front of me- but I have no reason to believe I am wrong) and it's not an add on -it's the only one. It's not the same as the toilet paper filter except that the filter lifts up out of the canister instead of unscrewing as a unit. All vehicles used to have a canister type filter back in the 50's and on into the 60's. I have a 63 GMC truck engine that uses just such a canister type- it holds 2 quarts BTW.
How can you be so sure it works if you're not using it-or never have used it. On a car that sees so little usage-what do you hope to accomplish?