Parallel? How do you set the VTA?

I don't change VTA when changing records -- that would require not only repeatable settings, it would really require listening and finding the ideal setting for each particular record. That would be a lifetime project.

I can hear the difference when I make surprisingly small changes in VTA by moving the arm up or down at its base. Whether this is really attributable entirely to a VTA change, or whether a small change in tracking force is also involved, is really an academic issue -- I hear a change regardless of the actual cause. But, I cannot see it being worth the effort to optimize VTA each time I play a record.

If differences in record thickness, and the resulting effect on sound, is that big a deal to someone, perhaps that person is a candidate for a longer arm -- the length will reduce the VTA change for any given change in height of the record surface.

I can’t see adjusting VTA for every album either. What happens if you change your cartridge? You’ve got to start all over with each album. Not criticizing those who do adjust for each album…it’s just not for me

The beauty of the ET2 linear tracking, air bearing tonearm (along with other beauties): easy (takes seconds), repeatable, VTA/SRA adjustments; WHILE THE RECORD IS PLAYING!

The magic 92 degree SRA number is only a starting point. From the original paper by Risch and Meier cited by Fremer:

"SRA, however, is generally 91 to 95 degrees relative to the record surface in order to facilitate lacquer "chip" (cutawaystrand) removal. Proper hi-fi set-up should therefore concentrate on cartridge' adjustment that has the tip of the stylus pointed "back" toward the tonearm pivot, and the top of the. stylus tipped "forward" so that the contact SRA face is 92 degrees between the stylus and the record surface.Such alignment will at least approximate correct SRA".

People will defend their favored methodology to the death. I generally agree with the OP; it's important to have a starting/anchoring point. However, it doesn't really matter how you start; it is only important to find a method that works for you to reach the happy end point. If you find comfort in measurements, arm yourself with a digital microscope. Others trust their hearing. As with most things in high end audio, there are precious few absolutes, only what works best for you.

Dover
I have a screw gauge that slips under the arm lift.
1/4 turn of the screw equates to 1/1000 of an inch.
I can hear 1/1000 of an inch like night and day.

Apparently, it takes a 4mm change in the VTA to change the SRA by 1 degree on a 9-inch tonearm, even more on a longer arm. If you can hear a change of 1/1000 of an inch in the VTA, that means that you can hear a change of 0.00635 degrees in SRA, even less if you have a longer arm. You surely are jesting, Dover!

The issue I have with adjusting the VTA for every record and writing it down like Doug and Dover do is that you might very well not have the same setting the next time you listen to that same record even without touching the tonearm. Ambient temperatures will affect the VTF, which in turn will affect the SRA. To illustrate with an extreme example, if Dover can hear a change of 0.00635 degrees in the SRA, a change of a fraction of degree in the ambient temperature would result in a change in the sound that he could hear. I suppose you could account for that by ensuring that the VTF is the same, but that's a lot of work every time you put on a new record, in addition to cleaning the stylus, de-staticking the record and removing any residual dust particles, removing and putting the clamp and the periphery ring back on! Unless you have a listening room that is perfectly air conditioned 24/7...