I drill with a bunch of people who range from UCI pro's all the way down. Everyone drops knowledge. Here are a few things that have clicked with me. One of the first things is you need to find your limits. Continue to drill turns in the field until you're rubber up. Even though it sounds like your tires are starting to cut loose, it may not be the case. Let that grass ripping sound become normal. When someone in our group goes down the comment that everyone makes is "THAT's finding your limits!". That positive reinforcement makes it easier to go down repeatedly.
It was once demonstrated that you can corner a turn with only your inside hand on the bar and only your outside foot clipped and under your body (not tri-podding) AND at speed. It seems that when turning correctly, your front wheel wants to turn in. HARD. If you're pushing forward with your inside hand keeping the front wheel from folding in, it's easier to guide your steering through the turn. So, weight on the outside pedal, pushing forward on your inside hand while guiding and leaning into the turn.
There is also the concept of counter-steer. It's best if I leave this to JPow:
http://www.cxhairs.com/wp-content/up...eCornering.pdf
Unlike road riding your weight is not always anchored to the saddle. There are many times that it's preferable to float over the saddle. This happens a lot in turns. If you let the bike float under your body while in the turn it tracks better, especially in off camber turns, but I find it pretty impressive in flat sections as well. Here's a guy who took it to the next level:
I try to doing speed checking while I set up the turn and going brake free through the turn. It took more than a few pre-laps to understand the course, but the turns are solid. This works well in off-cambers. Often the bike will wash out because of braking in the turn. Trust in your technique and gear makes for a more solid turn.