Are linear tracking arms better than pivoted arms?

Samujohn, the problem of the short vertical lever is independent of the bearing principle. Even a (purely theoretical of course...) very short pivot tonearm would face the very same problem. This has nothing to do with friction or bearing type.
Problem is, that most do assume, that a record is flat. It is anything but that. Even the very best possible pressings out there (King or JVC/Japan) are a nice landscape with countless hills and valleys under a microscope.
Thats why very long tonearms do provide - independent of cartridge or mass - kind of more stable sonic picture with more inner peace. They have less change in VTA/SRA.

Fascinating thread for me, as I just acquired a Souther SLA-3 the other day.
There has been some hot-tempered debate, some baseless opinion and some pseudo-science; all the elements needed for a real honest-to-goodness internet forum!
There has also been all the elements of a reasoned discussion for which I thank those of you involved on that end.
I look forward to the challenge of getting the best sound I can out my new linear tracker, I'll be experimenting with cartridges of differing compliance as well as differing counter-balance weight placement, etc.
I am thankful there is a marketplace like Audiogon where I will be able to purchase used carts at a big discount over new.
I am thankful Audiogon has this forum where perhaps with your help I will be able to maximize the pleasure I get out of my new arm.
And I'm thankful that if I despair of reaching cloud 10 and can't live on cloud 9, that one of you will purchase my Souther and carry on!

My understanding is that some stylus shapes are more VTA tolerant than others. This information should be available from the manufacturers, so one can see what range of VTA tolerance is needed by each arm. In any case, the records vary so much in thickness and in cutting angle that precision in that area is almost useless, unless one has a quick VTA adjustment and a notation on every record jacket. I really miss that feature which I had with my old MMT arm. Unhappily, despite that feature, it never really sounded all that good.

Dertonearm, if I understand you consider a short arm to be the Achille's heel. I can only offer anecdotally that the shorter I adjust my tonearm the better it sounds. I can think of no explanation other than that improved resonance control of shorter arm is of greater importance than maintaining absolute VTA. Designers of top pivot arms obviously give much thought to controlling vibration with particularly elegant arm tube compositions. But it is remarkable how many long pivot arms appear to be casually designed in this respect.(Based on appearance I would include Thales in this second group. I would also include any arm with a detachable headshell.) But all things being equal regarding arm tube composition, a short arm should win at least with respect to vibration control.

Taken from another angle, is it conceivable that micro-variations in VTA(which long pivot arms also suffer albeit to a lesser extent), are any more detrimental than out-of-tangency tracking errors with pivot arms?

Finally, what pivot arm approaches a linear arm in clean portrayal of inner grooves?

We need Jonathan Carr to chime on in this discussion. He designs cartridges for Lyra and used to post on some audio forms a few years ago. But, i can't remember which website.

I be he'd have a lot of insight to share on cartridge design, tolerances, forces, and tonearm factors.

Does anyone remember which audio website he posts on? I think his moniker used to be "J Carr" or something to that effect. For some reasons, I think he now only drops in on one of the DIY Audio boards.