Small Mercies

It turns out my instinct was right. I had used about 8 minutes on 6. ... Bg7, deciding that 7. Bxf7+ shouldn't 'work'. It shouldn't. It's not losing, but it shouldn't be winning, either.

Analysis by mrundersun:
8. ... Ke8 9. Ne6 Qb8 "Qb8 is better than Qa5 since white would then have Bd2" 10. Nxg7+ Kf7 11. Nh5 gxh5 12. Qh5+ Kg7 "I never realised that the Knight was trapped".

mrundersun(2012) vs SimianChatter(1768)
Position after 12. ... Kg7 (analysis by mrundersun)

And the moral of this story is...

(Predictably...) having an instinct for where the danger is or isn't is a good thing, but it's useless if it's not backed up with concrete analysis!