Setting tonearm angle?

Dear Islandmandan: +++++ "
In other words, I haven't noticed the necessity of adjusting overhang as VTA is adjusted. " +++++

the cartridge/tonearm alignment set up is critical to achieve the lower tracking error and lower tracking distortion. All the alignment " methods ": Baerwald, Stevenson Löfgren and the like has its foundation on the precise offset angle and overhang where any tiny tiny deviation on each of these parameters means higher tracking eror that means higher distortions.

That you be aware of those distortions or not is not the issue because that higher distortions exist if that overhang is not spot-on.

When you change VTA/SRA you change the overhang too out of its " ideal " set up and what you are hearing is not only ( as you said. ) " the improvement...by the VTA change " but a degradation on distortion level of what you heard because that overhang tiny deviation.
I repeat: that you are not aware of it it does not means is not happening. To be aware of it needs in deep training on how deviation on overhang sounds, so maybe you shoul start some method to learn about.

Regards and enjoy the music,
R.

I got a tiny bubble level for my Akito and set it on the flat top above the cartridge and levelled it. Seems to have done the job and the cart tracks perfectly.

The implicite assumption is that cartridges are made for
the parallel position with the record. The other implicit
assumption is about the bearings position in relationship
to the record surface. Those are, uh, theoretical assumptions.
The actual state or situation always start with: 'it depends...'
But VTA has only 3 possibilities: parallel, up or down.
I would say 'depending' on the position (angle) of the stylus
in the groove and the position of the coils in the generator
which depends from the VTF.

I have been looking into this recently, perhaps you should read Michael Fremer's articles on SRA and VTA. I suppose what troubles me is that in order to change the SRA by 1 degree the tonearm (9") needs to move about 4mm, longer arms more! This would put the bearings in a very unnatural position with respect to the record surface if more than a couple of degrees is required. So I don't have an answer, like you I'm searching for the truth/a solution. Just some things to think about, especially the magnitude of adjustment required to make a meaningful change in the SRA. Going by ear is fine if your baseline is close enough, you can tune the sound! but I suspect stylus and record wear may be a factor if the angles are way out. Please let me know when you find a solution.

If you want to demonstrate or hear for yourself what a mis-aligned cartridge sounds like-get a test record. I've been working on my setup's alignment over the past couple of days and think I finally have it "dialed in". The VTA's correct, the SRA is correct as is the azimuth and the amount of anti-skate and lateral balance. Before I corrected, my setup always distorted slightly during loud inner tracks. After I was sure the cartridge was mounted correctly (having used every template, etc. available), I was able to use the test record's test tones to fine tune the lateral balance and anti skate to the point of lowest distortion.
My setup passed all of the "torture test grooves" and sounds quiet throughout playback.