Hahaha sorry this response is super late as well hadnt been back on OS in awhile been busy. I have found out a few things yes holding Y triggers conservative body catches tapping it will make the receiver go up for the ball with his hands.
Yes I have been able to make user one handed catches but they seem to trigger when in proper position and haven't been able to trigger them by doing anything different myself.
To get a receiver to jump on a bullet pass you can move the left stick away from the ball and then towards the ball right as you press y.
Only problem I have now is turning around playing on anything higher then pro since offensive strafe is turned off on all pro and all madden.