I agree with TJ (aaaaaaaaaargggggh!).
If you form an unopposed “ruck”, you should remain on top of the ball to prevent the opposition from accessing it. If you go right over the top of it, then it’s fair game.
Even if a proper ruck has formed, if the ball is clear out the back and no-one picks it up, then again, it’s fair game (even for the original tackler/tacklee to get up and play it).
Blasting right over the top to clear players out is great if you’ve got support immediately behind you, but leaves you open to sneakiness if you don’t.