First of, a very useful link for a thorough and extensive website treatment of the gap theory which appears to be very sound from both a biblical and geological perspective:
Secondly, I'm puzzled as to why so much energy and time is given to answering the endless stream of criticisms from the "anti-Gap Theory" people ?? Each time I click on what sounds like a promising web address, I am often greeted by long streams of verbose apologetics......as though this were necessary in such great length and detail?
I would love to read more that simply launched into the fascinating depth of its implications without much further ado. I have totally accepted the existence of the time gap between GEN 1:1-2, and the catastrophic events only touched on by the original Hebrew from which the texts are derived.
I still live in hope of finding such ! But all encouragement and God's blessing of continuing wisdom and revelation, as you endevour to reveal what God would say.