There's no question that a LT's ability to reduce tracking angle distortion to near zero produces superior sound, provided of course that all other things are held equal. The problem, of course, is that all other things are NEVER equal.
To take one example (borrowing from Syntax), I haven't heard the Kuzma 4P but the Airline was sonically bested by a Durand Talea (which is not a LT) in a comparison I attended a few years ago. We used Ortofon A90 and ZYX UNIverse, trying both cartridges on each arm. All five attendees agreed that the Talea reproduced dynamic and complex music significantly better than the Airline. The advantages of the Airline's lower tracking angle error were swamped by the Talea's greater clarity, micro-dynamics and lower sound floor.
In in a complex system like vinyl replay, focusing on one parameter while ignoring others can impair overall performance. What one wants is the benefit of LT without the mechanical complexities of air bearings, servo mechanisms and other contraptions. All of these, perhaps inevitably, raise an arm's noise floor and sound floor, impairing its ability to get out of the way of the music.
I've no doubt that Syntax is correct that the 4P is bested by the Airline. The 4P is also a complex assortment of contraptions. It probably has a higher noise and sound floor like the Airline (compared to the quietest arms) but without the benefit of LT.
This is - obviously - a long-winded, back-door vote for the brilliant concept behind Frank Schroeder's LT. I've not heard one, but it appears to address the above issues rather neatly. Frank's top tier arms have always had a superbly low sound floor (while being a bit soft on dynamics). His solution to the LT function doesn't seem likely to raise the sound floor by much, while its captured bearings should provide superior dynamics vs. his "string" bearing arms... the Schroeder LT may be the best arm I've never heard. ;-)
