The way I see it there will be a decent pressure drop within the...

The way I see it there will be a decent pressure drop within the reservoir, much of it occurring within 1cm of the fracture faces (P Basinski). From there it will remain in gas phase until it gets the opportunity to cool and not much cooling will happen short term while it is surrounded by hot rock. Its environment will off set the cooling Joule Thompson effect on a depressurizing gas.
The pressure drop is going to be high with gas lift dropping the column weight, conceivably close to double that applied last time.
The gas which is really super critical fluid, will therefore expand and reduce density leading to greater flow speed but lower mass flow
I do agree once its in the production tubing we don't need to worry about it, my comments were in relation to what is happening in the reservoir itself
On the volatile oil phase envelope, I haven't got one that fully matches either, retrograde condensate does however and I suspect the HRZ is in the transition zone between the two.