If you can't control your low back, you shouldn't attempt the position. It's likely that the root is that you're trying to go back further than your flexibility allows -- if you do that, you have to make it up by bending at the back or the knee. Even when someone exceeds their capacity in the former, it almost exclusively shows up in the upper/mid back rather than the low back.
In the same way a back is held in extension while moving forward at the hip, it can be held in extension while moving the torso backward at the hip. I think all of you guys will concede this can be done for a certain ROM, but have a problem seeing that the same thing is happening over a larger ROM in lifters who are more flexible and who have the athleticism to pull it off. IOW, if you can't control hyperextension when you press, you need some coaching, you need to get stronger abs, or you have no business attempting this advanced version of the lift. I'll be posting vid of differences in position in a bit. Rip says I am wasting my time, but it will be helpful for those who are actually willing to learn and just need some help with seeing what is going on from a remote situation. It's a lot easier in person as someone can simply feel the back position stay the same during the movement.