Are cutting lathes VTA constant across the board?

what Dover said….. even the lead out groove…..

I thread is usually enough.

David Shreve, Guru on this topic, published these adjustments a long time ago using Rabco arm of 7 5/8"
 +/- height
Nautilus            +0.0058"
RCA, Vanguard        +0.0047"
Columbia pop        +0.0043" 
M&K RealTime        +0.0019"
A&M, Arista, Flying Fish, Performance Recordings, Warner Bros. 0.0000 
Telarc              -0.0012" 
English Decca, DGG  -0.0028"
Nonesuch            -0.0036"
Musical Heritage Society (some) -0.0085"
Columbia classical -0.0118"

I'm sure it's important but once the cart is set, I just play the disc. 

I adjust VTA for

1 - normal records - using favourites

2- 180g records - using favourites

Then jut run the 2 settings.

All my arms have VTA on the fly - but I run the 2 settings - otherwise you would go insane.

Unfortunately, historically cutting angles are all over the place - USA/Europe - then individual pressing companies vary a lot.

Furthermore, as regards RIAA standards - thats another story. Varies from recording studio to studio - some engineers compensating for the turnover frequency issues, some not, all dependent on what cutting amplifiers and heads were used.