Hi BW
Which clinic does David McKnight work out of? I'd hate to go against what your GP wants but unfortunately, as great as our GPs can be, they still really don't know much about infertility + autoimmune problems.
If you suspect you may have immunology issues, and it sounds as though you may have grounds to, it makes sense to go to Gavin or Dr Matthias. Otherwise, if Dr McKnight is not a believer in this, you'll only be wasting more time and $$$ going around in circles. You'd be killing two birds with one stone by going to Dr Sacks - infertility + immunology.
Not sure where you live but he works out of IVFA Kogarah (St George Private I think) and IVFA City. The city clinic is too easy to get to, it's above Wynard Station. You'll need to go to St George Public Hospital for the final BT.
Good luck, he is a lovely man.
PS I don't get a commission from Gavin for recommending him either!!