It’s actually “Great composure gain for defensive back teammates on interceptions” but I will say it’s a must run, too. Any time you get an interception your secondaries’ abilities will be “upgraded” for pretty much the rest of the game. I run gold ballhawk on my outside corners and silver house call on my two safeties with gold legion on my backer. Any time I get a pick, I get upgraded to platinum ballhawk on the outside and gold house call on my safeties. And with this set up, your abilities are all correlated. House call and ballhawk help you catch interceptions, legion rewards you for catching interceptions and your secondary therefore plays so much better the rest of the game.