It lets me set high and low limits and trades within that range without further input.
It could be improved by allowing a setting that says put buy orders 3% below last trade and sell orders 3% above the last trade, or whatever range is thought best.
As it is, it allows the market to move and your price stay the same ending in being trapped on the wrong side of big moves, but other than having to keep a closer eye on it when markets are moving, it runs mostly unattended.
Mine has paid for itself multiple times over.
At least, it did before the volume dropped out 2 summers ago.
RE: Witness update