When does recall typically happen, if at all? Countless of times, and many reasons. There are quite some humbled traders who have gone wrekt when a Broker, Clearing House, or Government Regulation Agency suddenly announced a particular instrument is no longer marginable.. How now brown cow? Did you factor THAT risk in?
Don't see how you can have a viable system with stocks that have buy in risk... The borrow costs alone seem prohibitive.. Im assuming he's not trading reversals thinking there is an arb..