I watched England training at Twickenham last week in their "Open Session" and while I wasn't particularly impressed with much of their training (!) there was one practice from Mike Ford, Defence Coach which has had me wondering.

In 3s they were practising the following:

Ball carrier approaches tackler. Tackler A performs side on tackle, while at the same time Tackler B (on feet at all times) goes for the ball. (so far, same as Angus' "Immediate Jackal")

Now, let's assume that Tackler B releases for a fraction once ball carrier hits the deck, to take out the thorny issue raised in the above thread. Tackler A gets up and is entitled to play the ball from any direction - in this drill they were practising getting up and staying low, facing own posts. Tackler B is facing opposition posts.

You have no ruck formed as no other opposition player has arrived competing with them over the ball, and you now have 2 players from the tackling side over the ball, facing each other. In effect they are "shielding" the ball making it very difficult for the opposition to even see the ball. When a supoorting player was coming in to this situation, they found it very difficult to compete for the ball indeed.

There are to me clearly ways that sides could manipulate this "tackler playing the ball from any direction" even more effectively than South Africa and their Provincial sides embarrassed the Lions with it. If both tacklers look as though they are competing for the ball (legally, as no ruck), then sides will find this a real problem to counter.

Any thoughts?

Watch how a good side on tackler tackles with his head in front of the ball carrier, at ribs height. Momentum will help land "in front" of the tackled player, allowing him to get up on the wrong side.

But as to my original post, is it legal for the backside jackler to shield the ball in this position, if he has no intention of playing it? 

ie just getting in this position to get in the way so that the "forward facing jackler" can get it unimpeded?