just finished reading commercials
anyway -- better reading is How to gain gain_A Reference Book on Triodes in Audio Pre-Amps.pdf from Burkhard Vogel
as I see it - that's classic mu follower stage , where both SS Jfets can be objected with their respective source resistors as two identical active elements , where value ( say - equal ones , for start) of source resistors are chosen mainly in role of transfer characteristic shaper ;
then "drain " resistor of lower SS ( or lower resistor in centre of totem pole ) is used as core of modulation apparatus for upper half of mu-follower
changing values of these three (groups of) resistors will lean transfer characteristic of upper part of mu-follower output stage to more "triode like" or more "pentode like"
there is also fact that - when decreasing value of lower SS source resistor - we must decrease value of it's respective LTP drain resistor , that way also altering value of OLG of entire amp ........ that way altering amount of NFB ...... that way altering slew/rise/damping factor/etc. ; so - differences are mix of several various factors
in any case - matter of preference , same as bunch of ppl divided in odd vs. even harmonics thd spectra liking/willingness to bear with
I know some who are fans of disconnected Aleph CCS modulation , same as I know some who can't even think of that ( I'll not mention some who aren't able to bear Aleph style amps at all , even if they were willing to flip entire A amp in polarity , from some reasons - somewhere in dark ages )
conclusion - feel free to play with amount of upper part of u-follower contribution , same as nature of transfer characteristic of OS of amp ........ but don't expect others to follow you blindingly in those deepness of twisted pleasure