In terms of trigger movements, what's written in textbooks now as a forward press has its origins in how the subcontinental masters look to play spin. It can be very effective for that, but if applied recklessly, you will play around your front pad probably more than is wise. Many great batsmen and batting experts advocate the back-and-across movement because it brings the body into readiness for playing straight, whether back or forward and can be helpful against sharp pace bowling.
It's also interesting to look at players with really unorthodox stances like Chanderpaul and Katich in this regard. While both his feet take a complete step across his stumps, Katich opens his stance just a little to play the ball. Chanderpaul on the other hand takes a very small step with his back foot and usually a bigger one with the front, closing into a more orthodox position from an obviously quite open stance.
