I have yet to get justification to spend hundreds of dollars, for a little bit better tune ...
Is it worth the cost? I still don't know.
You sound pre-biased against it - almost as if you don't REALLY want to know ...
You've clearly never driven a vehicle before-&-after a tune - otherwise you'd not say
'little bit better'.
PCM tuning (ecm & tcm tuning for younger vehicles) is not ONLY for 1320-type enthusiasts.
Drag racing is wasteful FOR ME, but I appreciate objective measurements.
Speaking of objective measurements, I get BETTER MpGs since having my pcm tuned.
Though it can also be quicker than a typical '02 Tahoe Z71, when my foot gets down.
Usually, though, better MpGs, especially on the highway.
FYI, there are enthusiasts at the other end of the spectrum known as 'hypermilers'.
Once they re-learn how to drive to exceed gov't MpG estimates (by sacrificing time), they typically resort to pcm tuning to further improve their MpGs with greater consistency.
If your major concern is MpGs, mention that to the tuner.
You'd clearly be pleasantly surprised at how much can be done to tune YOUR pcm to suit YOUR tastes and goals (especially applies to vehicles that use our particular pcms).