Re: colouring

>> This, if course, brings up the question of how one would prefer to notate
>> the sequence *oH2 where we expect an *o-quality in the absence of the
>> 'laryngeal'; I guess I would prefer *oH2 but I assume you would want
>> *aH2?
>
> This has been discussed a lot in the literature. The bottom line is that
> *o, unlike *e, was not coloured by an adjacent *h2

This is self-explanatory: what /h2/ does is that it backs front vowels,
and because /o/ is already not-front, nothing is changed.

> (neither was long *e:, for that matter).

This is less understandable;
the /e:/ from contraction could maybe be seen as /ee/ coloured to /ea/ and
then conracted to /e:/, but why was not coloured /e:/ from compensatory
lenghtening?

P.A.