get yourself the tree climbers companion by Jeff Jepson... shows you how to tie a block with cow or timber hitch. Line gets tied to top with clover hitch locked with 2 half hitches or a half hitch backed up with a running bowline.. Never cut one handed and push with the other... learn how to make a clean notch and back cut to control the movement of the piece. Drop the saw , then push with 2 hands if needed.. If you cut a narrow humboldt notch instead of an open face or traditional, there will be a lot less "pull", that is force to sway the top. As the narrow notch closes early, before the piece gets too much lean.. its all that lean, when it stops for a moment when the face closes and before the hinge breaks, that causes so much movement in the top.. Keep the block close to the cut, & use a line with a lot of stretch (ie Sampson's true blue).. These are things you can control as the climber. Most important factor is certainly how well the groundman lets the piece run, however, that is not necessarily something you can control.
You have no idea of the amount of force that can be built up when dropping large loads on a static line, which is basically what you did.. the force multipliers on that cut were big.. you got away with it because the piece was relatively light.. don't try that again... If there was some hidden defect in the trunk, that much force could cause the tree to fail easily!!! Learn all the above stuff as though your life depends on it, becasue it does!!!!