He's had 2 goes at it. I think that's enough. Especially considering that he has no experience with virtual surgery planning or downgrafts. It almost sounds like you'll be his first patient on whom he will try these. Before I had my surgery I got cold feet and consulted with another surgeon, who did nothing but praise my originally chosen surgeon. So I stuck with the "best guy in the state", who then proceeded with the laziest, sloppiest surgery possible. BTW, he too does not believe in downgrafts and doesn't use 'computers'. That old semi-retired guy simply had nothing to lose by recommending you to go back to your original surgeon (BTW, was the old guy's name David David?) It's not like he has to live with the consequences. Professionals like to praise their alumni. Unfortunately max fac surgery in Australia is bush league. So it's just one bush league champion praising another.
I think the real reason why he "wants to have another go" is that your bite may be off. When I consulted with my butcher he got more and more weary and irritated by my constant questioning, especially regarding the aesthetic consequences of the surgery and blurted out "at least you'll have a good bite". That pretty much distils the "philosophy" of Australian surgeons - "it's a bite fixing operation". To them we're just meat bags with dental arches to be matched. The bite is the only obligation they think they have towards us, nothing else - not tooth show, not symmetry, not facial balance, nothing else.