The oil was run almost 6,000 miles under severe conditions... lots of cold starts with short drives according to the OP. Most automakers recommend 3,000 to 3,750 OCI's for "severe" service, and this OCI was almost twice that long. The TBN was still 1.6, and wear numbers were well within acceptable limits despite the fact that the OP used an oil grade that is not recommended by the OEM for that particular engine.
It seems to be the common consensus around here that dino oils should hold up well for 4,000 to 6,000 miles under severe conditions, and as much as 8K to 10K under ideal conditions in most vehicles. So... what, exactly, is disappointing about these results??? I'm at a total loss here.