Daniel Snyder: But lets say you moved a piece 2 turns ago, so I know a piece is there - but it is "black" again - Then the computer would let me jump the piece - and if the computer lets me jump a "black" square - then I know just from that where the pieces are.

It would not do nothing then make extra work to keep track of where the pieces are, and the notepad NEEDS to be moved to above the game before that happens.

But I don't see how Dark Halma would make anything different from regular Halma - other then more work to keep track since your opponent can still easly keep track of where your pieces are.