Rugby: Defensive shape-using 4-man pendulum

Description

Our defensive system works with a 4-man backfield. We put an extra man for covering/counter attacking. This gives both wingers less responsability to come up and cover at the same time. Using 10 as a second fullback gives more vision and decision-making for counter attacking. Also the best kicking game in the team. The ideal will be if we have a left-foot 10/15 and a right-foot 10/15 in each side.

We only use the 8 forwards and the 2 centres in the defensive wall. Faster players in the outside, slowers inside. We only use 2 players in the breakdown (tackler and jackler), and usualy 3 at rucks in the wide channels (because there's only one side to attack, so more defenders can drift to only one side). 

The wingers come up after they read the direction of the attack. That gives 3 players in the back everytime (one for box kicks/parallel kicks, one in the middle and one for the cross kicks).

Number 9 works as a sweeper. He will order the breakdown/breakdown captain (he will call to leave and play the next ball or attack the breakdown). He will also work as a relief for first defender if there's need to do that(he always relieves the blindside guard/A role, as there's no need to cover a short kick because there's alrealy a player in the back covering the box/parallel kick).