Regarding flight testing and data gathering, I think it's pertinent to point out that Capt. Wainwright's paper was published back in 1999, and while he is absolutely correct in what he says, recent events have caused something of a shift in how both Boeing and Airbus approach stall testing:
AF447 and similar incidents have effectively proven that in certain circumstances, teaching "approach to stall" simply isn't enough. And while simulators will not be able to mimic the real aircraft's behaviour entirely, I can't help but think that instilling a general feel for the process of stall recovery at least can't hurt.