"Bounce levels" in the S&P 500 (SPX) will depend on where markets close Friday, says Charles Schwab's Joe Mazzola. Market breadth isn't helping push back U.S.-Iran volatility, as Joe points to less than 50% of SPX stocks trading above their 200-day SMA. He's waiting for a market "flush" before fear can truly begin to trickle out of markets. "It's hard for investors to place where they can hide," says Joe, noting headline-by-headline volatility constantly shifting market direction.