Pronunciation?

[David Sanchez]

Another doubt on pronunciation:

3) D. Tuggy metions that to words endding in final vowels are pronounced
with an extra non-phonological glottal stop. The rule that vowels preceding
glottal stop and in final possition are shortened supports this claim. But
if:

choca 'he/she cryes'        is uttered        [tSo:ka?]

What is the phonetic (non phonological!) difference between <cho:ca> 'he
cryes' and <cho:kah> 'they cry'.

Thank you, in advance
Davius