Tournament Set defensive squad

You're opponents get less points against you.

Not much. Only a few could take advantage of your squad. Atm there are 2 things that determine tourney winners. 1) Who has the most ally points and slightly less important 2) Having more than 1 meta squad that allows you more points per ally points spent. By throwing in a nothing squad you allow a nothing squad to beat it... basically giving free points to those that find you.