Especially when compared to the other feats at level 15. There are already many ways to replenish or sustain toughness with other classes, which leaves this feat redundant. It also creates an odd incentive to shoot on a horde that teammates are in melee with, incorporating a risk of friendly fire that damages health instead of toughness. Veterans won’t always be shooting the same horde that’s being fought in melee by the team.
Covering fire should be reworked to provide an offense based utility like the other talents at 15, or replaced with something more useful.
Maybe if it gave everyone in coherency toughness but even then generating more toughness while in melee is redundant because that is when you get more toughness in the first place.
Maybe change it to granting toughness to allies when getting headshot kills so you are rewarded for “covering” your melee mates from the guns shile they are in the open.
Like maybe (and would need to test it) if it worked from grenade kills then i get it, because grenading a horde would fill the toughness of any nearby allies.