Flash hit the nail on the head with this one. Worrying about the strength of the hip flexors is going to be counterproductive for most. Although, I’d be more concerned with the excessive tightness of the hip flexors reducing the power output of a whole host of other muscles (rectus abdominus, external obliques, hamstrings, glutes).
And like Lyle said, doing a couple extra drills or stretches at practice is unlikely to correct the issues. The math won’t add up.