MJR> But who in the heck designed Pinyin?

RB> A committee of the People's Republic of China (it was
RB> approved by the Communist National Assembly in 1958).

Ah, design by committee.  That explains much. :)

RB> Gwoyeu Romatzyh (in Pinyin that would be written: guóyŭ
RB> luómăzi)

minor point - you're using breves for tone 3.  I thought Pinyin used the wedge?

MJR> Some of those assignments make no sense - |r| for /z`/?

RB> Except that in the Bejing dialect the sound is retroflex [ʐ].

That's also what CXS /z`/ denotes.

RB> |r| was used this way in GY also (I'm not sure about
RB> Ladinxua).

Interesting.  Is there something rhotic about that sound which I'm imissing?

RB> Yes - we can all come up with our own schemes - I've done
RB> it  myself many times. But I do think one ought to leave it to
RB> the Chinese.

I have neither the desire nor the /' to replace Pinyin with a
scheme of my own devising, even in personal use; I was simply placing
myself in the role of designer to try and better understand the
choices that were made.

RB> The use of |q| BTW for [tɕh] comes from Latinxua and was
RB> adopted because lower case |q| looks vaguely like Cyrillic Ч.

That makes some sense.  Thanks.

MJR>  I think I'd have better luck learning Maggel. :)

RB> Rather unfair IMO - Pinyin is systematic & regular in itself.

My statement was, I thought obviously, an example of (intended-to-be)
humorous hyperbole.   Nothing could be as difficult as Maggel - by
definition, IIRC. :)