So i was leafing through a book called Blackjack for blood when I came across a section intitled "what to do if thea dealers hole card is known." He said that if you knew what the dealers hole card is you would have ~10% advantage. I looked through the tables for MH ( min hard hand total to stand ) and MS ( min soft ) and found that the numbers are very close to each other ( comparing MH to MH and MS to MS ).
So I had an idea...what if, just what if, in a positive count, you asume the dealers hole card to be an 8 and in a negative count you asume the dealers card to be a 7? I scanned down the list and found that the strategy for hiting when the dealers hand was X dealer card + the asumed card was only off by a min standing hand total of 1. For doubling and spliting you can make adjustments based on what it says for the majority of X + MH or MS hands to do.
I know that die hard basic strategy players will dismiss this altogether, but i think that it is worth running through a sim.
Joe- You may find it interesting to look at the wizardofodds.com site under BJ appendix16. It gives you all the proper plays when you know the dealer hole card. The dd's are very interesting, but they all assume that you know the dealer hole card exactly.
There are some methods that will allow you to know the dealer hole card within some range (say 2-8) over 50% of the time, but not exactly. The problem with arriving at this bit of knowledge is that mistakes exceed being correct and you need to be correct much of the time for any PE to beat a BJ game.