Thanks for all the detailed answers @chris, I really appreciate your explanations (I´m pretty aware some of the questions dig into bits of the code written long ago). Most of my doubts are clear, just a couple of comments below.
Regarding the humidity and EN-15251, I think that is the only paper I´ve seen attempting a correlation. Nothing has changed on the standards as far as I know.
As for the effect of air movement, I understand that the upper comfort thresholds are modified to account for the cooling effect of air movement. Both the CBE tool and the hydra definition have helped me trace it back in the code to:
Is that the formula for one of the curves described in ISO 7730 annex G (below), or something else?
I haven´t found any source on CBE´s website either.

