analog newbie question/vinyl weight

Interesting thread and interesting comments how different vinyl thickness effects VTA and subsequently the sound. Reading Fremer's piece in the June 2010 issue of Stereophile, a difference of 1mm in record thickness has an insignificant, if any, effect on VTA and therefore sound. I quote:
"A change in VTA as small as 1 degree requires a rather large (4 mm) vertical displacement at the pivot point of a 9" tonearm, which is why one online story, about using the thin shims included with the Ringmat system to 'fine-tune' SRA, is sadly misinformed. Use of all eight of the supplied shims and the total height change is 1.255mm, which represents a change in SRA/VTA of about 0.29 degree for a tonearm of 239mm effective length. Sorry, but once you're properly locked in at 92 degrees [he's referring to SRA], you're unlikely to be able to hear a difference of 0.3 degrees!"

Since the difference in thickness between a 100 gram and 200 gram record is 1 mm, this should have no real effect on VTA and therefore sound. This begs a question what those who claim it does have an effect and adjust VTA for different vinyl thickness actually hear.

Just off the cuff.. I think changing the record height or thickness will change the SRA much more than changing the pivot height a similar amount. It is early though.

I'd say one millimeter is one millimeter on either end, and change in VTA is a change in VTA. For simplicity, if you started parallel to the record surface, I don't see how one millimeter on one end could result in completely different SRA than one millimeter on the other end, except that they would work in opposite directions. But I've been listening till 5 am and doing extensive damage to my Scotch reserves so someone with a clear brain please chime in.

I just checked, and Mikey's math is correct. A 9" arm describes a circle with a circumference of about 1,436 mm. Since there are 360 degrees to a circle, that would mean 1mm translates to about 1/4 of a degree.

As legendary as Mr. Fremer's listening acumen is, however, in this case he doesn't substantiate that the 1/4 degree difference isn't audible. I have a tonearm with very easily adjustable VTA, but it's only a 6mm range. That's only about 1.5 degrees of total range. Why bother if it's inaudible? Yet I often raise or lower by 1 to 1.5 mm to get a little more transient attack (higher at pivot) or more fullness and less stridency (lower at pivot). I also have noticed that my 200g pressings tend to sound a little rolled off and bassy unless I raise the arm about one mm.

Adjusting VTA to get more fullness or upper frequency extension is certainly not a novel idea, and if I had a tonearm that allowed easy adjustment, I'd probably experiment with it. However, most tonearms don't allow hassle-free adjustments; I have to loosen and then tighten 2 tiny screws on my Classic tonearm to change VTA. If I wanted to get VTA "right" for every album I was listening to, I'd be doing more adjusting than actually listening. This plus the fact that you don't know the precise angle of the cutter head for every single album make VTA adjustments seem rather impractical to me.