Drew with an IM, but was it a win?

Today the Kolty Chess Club held a Simul against Emory Tate.  There were 28 boards, and at the time I left, the club had achieved 3 wins and one draw (me).  Mr Tate offered me the draw in an interesting position, and I think it may be winnable... what do you think?

Hmm, it does kind of look winning -- what's white's risk to play on (besides facing a higher rated opponent of course ) but I mean only f3 is weak.  It seems like after pushing the a pawn and tying a defender to blockade it, you can just walk you king to c6 and go from there... so what's a defensive set up for black?  Blockading on a8 is too passive with either piece IMO, and the bishop can't make it in time so it seems like (I may be wrong) a6 is the only other option, and that seems weak.

So at first glance the seemingly most principled blockade would be Nc7-a8, but that should lose... I don't see an active defense so yeah, my initial impression is that white is winning.

Oh, wait, it's black to move?  He offered a draw without moving? hehe.  Ok, well Bh4 may get him active enough, if the bishop can help on the queen side then that should be enough to secure a draw without too much trouble I think.

Of course, I'm not looking at any concrete lines, just sort of philosophising about the position...

hmm, I'm pretty sure he played something else, but I'm not quite sure as I didn't write the last move down.  Maybe Bd8 or Nc7? 

Hm, I'd have played on as white for sure. The onus is definitely on black to show this is a draw, IMO.

I have seen Tate's games, he is a wild attacking player, especially in the Sicilians.

From my point of view I saw that Black win at ending pawn. Except if it is played with timer and run out of time then I will choose to play white as it has clearer position to play. But anyway I like the "Wild game" like that. :)