*nod* When Bruce tried to 'out' himself to Gordon in NML Gordon turned his back and told him to put the mask back on. Even going so far as to say 'if I wanted to know who you were I could have discovered it 10 years ago. And for all you know maybe I did.'
Which is as close to an admission as we're ever going to get that Gordon knows who he is, but won't officially let himself know it.