Here is a 1 minute chart of last Fridays action featuring Slow/Fast Stochastics, some trend lines. I am more inclined to believe that Stochastic is one of THE primary indicators of O/B-O/S levels during the day. If you think about it, you have your S/R lines (lots of them), but how do major players pinpoint the level at which the price has reached a temporary extreme level? I know that Stochastic is not "bullet proof", it does become a lot more reliable when one combines it with other confirmations and of course experience. In my experiences stochastic, if read properly, offers good overall signals of O/B-O/S intaday levels, we are talking 1-2 point plays, which sometimes do lead to more gains.
EDIT: changed the chart
EDIT: changed the chart