I was satisfied, but I did insist on getting what they should have just done from the start.
Disclosure: I work for Seagate but not in customer support but I do know some stuff about SMART. I am not an expert so I won't answer any questions but I do feel I have a different perspective to share.
Incorrect or invalid SMART interpretations are one of the biggest issues with "no problem found" failure returns. Often it comes down to third party software that isn't following the protocol and starts throwing red flags with the presence of raw counts. That is why Seagate support is asking people to run the Seatools software because it's written in a way to separate garden variety errors from catastrophic issues.
SMART does a great job, maybe too good of a job, in recording ANY and ALL aspects of drive operation. For example, raw and seek errors are a natural occurrence with disc drives and not a sign the drive is failing. The drive ECC is designed to correct normal bit errors and the user can sleep fine. Unfortunately people dump their SMART history and panic because they see numbers all over the place. Bad third party software will interpret these numbers and flag them as a problem when they really are not a problem.
If there is an inordinate amount of raw errors in a particular sector, the drive will map the sector out and reallocate accordingly. I have drives that reallocated early in their life and never was a problem thereafter. I had other drives that kept reallocating sectors until SMART finally flagged the drive as failing. Why would correctable errors start showing up after factory pass? It could simply be the conditions they are operating under at the end user. Just running in an elevated temperature environment can expose a weak area of the media that ordinarily is fine at lower temps.
I get the fact that Seatools is Windows only and not everyone wants to bother finding a Windows box and a USB/SATA adapter. Unfortunately that is the best software to determine if the drive has an onset of a lethal condition.
I'm not passing judgement about the situations I have read here, just informing people that you should be careful in the interpretation of SMART dumps and why Seatools is considered the proper way to diagnose the drive by Seagate Support.