I don't see how you can do this with HU. I don't know about the other people, but to me my actual cards only means something for that one big pot. My preflop play has more meaning for future hands than the current hand unless it's a huge hand(the one big pot), in which case the preflop play is determined by how I set it up from my previous preflop play. My postflop play is completely read dependent and has nothing to do with the strength of my hand.

I'd need at least 15 previous hands to determine how I'd play one hand preflop, and postflop I'd need the whole history.