<<BTW, I've been wondering anyway, how a conlang constructed by English
speaking people includes 'rough' sounds like that /x/
Don't they show kind of a masochist trait? ;-) >>
No, just a practical one (disguised, as often with JCB, as an empirical
discovery). We needed another sound, we were misrepresenting a lot of
language contributions by lacking an /h/-ish sound, we needed a sound that
would be distinct in usual channels (as ordinary /h/ is not) and, lo, we
found that most languages had a /x/ but not an actual /h/. And so, /x/ it
was.