Most significantly we use a different control system for the TA's position, which will greatly improve tracking accuracy- and it should by any given progress in technology-but we add some "special sauce" which should give the current competition a run for their money
Because of the short TA, the "bridge" that holds the TA completely straddles the record during play and moves motorized along tracks backward to enable changing the record- handy!
BTW a Rabco SL 8 arm, which I believe is similar (?) quotes a 1/6 of a degree tracking angle deviation. at an estimated 20 cm (8") length this translates to a 0.058 mm or 58 micron control span- impressive! (total +and -)
If adjusted properly, a T3F should not be off from perfectly tangent for more than half a groove. My Goldmund is a bit different from standard. I worked with DJ Kasser from Black Diamond Racing, a great guy who recently passed, to fabricate a carbon fiber plinth and chassis, Newport Corporation for a fully active pneumatic suspension, and a power supply company from England for a linear PS for the Pabst motor. We did this for an article I wrote for The Audiophile Voice in the 90s on turntable design. I encourage you to check out Newport’s suspension products for your design. Their pneumatic feet rival Vibraplane for isolation and provide perfect self leveling while the tangent arm traverses the record. They are really sweat, and can be run off a pressurized air tank. No loud pump required!