The Interactive Diagram estimates the sWAAF stronger than a Bishop. I suppose this has to do with blocking of the slider move. The Bishop might appear to have many more moves as an Alfilrider, but the extra moves are all very distant moves. The larger the board, the more distant they are. And on a board that isn't empty, but 25% filled (as the Interactive Diagram uses for value estimation), those very distant moves will almost always be blocked. So it is much better to have the unblockable sWF steps of the sWAAF.
That doesn't explain the good performance in the mentioned end-game, though. The board there is so empty that the Bishop only rarely finds two pieces on its diagonal, so that blocking hardly occurs.
The Interactive Diagram estimates the sWAAF stronger than a Bishop. I suppose this has to do with blocking of the slider move. The Bishop might appear to have many more moves as an Alfilrider, but the extra moves are all very distant moves. The larger the board, the more distant they are. And on a board that isn't empty, but 25% filled (as the Interactive Diagram uses for value estimation), those very distant moves will almost always be blocked. So it is much better to have the unblockable sWF steps of the sWAAF.
That doesn't explain the good performance in the mentioned end-game, though. The board there is so empty that the Bishop only rarely finds two pieces on its diagonal, so that blocking hardly occurs.