Stop loss is part of the money/risk management process that is the most critical part of investing. Without risk management the trader will go bust.
Put simple a stop loss keeps a trader in the game.
The bad news is that stop loss is not an exact science, there is no perfect methodology and as such it continually tests traders emotions and ability.
Warren will use his years of experience as a trader of geared and ungeared products with literally thousands of triggered stop losses under his belt to help those attending improve on their stop loss methodology including such issues as slippage, missing the stop, triggering intra period or end of period and over night gaps.