quarter

[Prof. Roly Sussex]

This has been an enlightening (for me, anyhow) discussion.
We seem to be dealing with
(a)     phonological/phonetic issues, especially how rounded
the "o" vowel is, linked to AmEng regional variation, vowel
inventories and related matters;
(b)     semantic-grammatical constraints (with numbers?)
(c)     pragmatic issues: transparency through context, familiarity
        of the phrase, coupled with speed

It seems to me that the degree of roundedness of the vowel is
important, since it will tend to labialize the /k/. But is
there additional labialization caused by an intervening /w/,
however short? This thought is prompted by the difference
between Russian /kot/ and Polish /kot/ "male cat". The
Polish version, give or take aspiration and a dental /t/, is
close to a British "cot". The Russian one, with the strongly
rounded Russian /o/, often sounds to learners like "kwot",
and that is often the best way to teach the labialization of
the /k/.

The other odd thing is that I haven't yet found a mainstream
dictionary of any variety of English that lists anything but
/kw/.

Roly Sussex
The University of Queensland