Most of the LB status comes from the horse's strength. Truthfully, FRing the foals isn't going to impact things that greatly. If he has enough good foals on the ground, those will compensate for any junk ones he might produce
I geld for gelding quests, geld and fr any Colts breeded that are under my standards, so to preserva my studs status. I's cheaper to buy yearlings for showing from other stables