The stat wire is usually tywrapped to the Carflex here, still a violation but not a safety hazard like taking it through the disconnect like you would have to to get it inside the flex.
No they will not let them use RX in the outside wiring, even if they do strip it. If this is new construction the EC runs the RX through the wall to the back of the disconnect and the HVAC installer puts in the whip to the AC with THHN in it.
On a retro fit it is whatever they can get away with. I imagine if the HVAC guy is doing the whole thing it might all be Carflex with THHN/THWN in it since that is what he has on his truck.
If I was doing a retro in one of our 2:12 - 3:12 attics I would fish smurf in the attic (you are not walking around up there), put an LB on the gable end and RNC down to the disconnect, pulling THHN/THWN all the way
I have been away from this for over a decade but when my wife was selling AC systems the permits were pre-approved deals that they just phoned in and inspection was a spotty thing.
