Let's put it this way, I don't even know if I've ever bailed on a rail from leaning forward too much.  However, I was in the same boat as you when i started sliding and corrected it by following the same advice JD_May just gave you.
Think of it this way, if you lean back, you're going to bail 95% of the time, if you lean forward and commit you'll probably slick it.
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This has been One Man's Opinion
'Too many rookies, not enough pros' Roy, as we watch our friend Dave try to have style
'What are they gonna do?, show us up, (followed by a lot of laughing)' Roy and I having a convo between ourselves wondering what would happen if a couple boarders in our park got mad
'I could be skiing right now.' Me in my friends car with some ladies at about 12 for lunch, they're singing, I'm bored, they weren't too happy, but they got the message and I went skiing sooner than I could've hoped
'hey baby, it's no good if your friends can't have none' My friend Dan, as he attempts to share and mack a broad at the same time