i have never really tracked it. i regarded it as better than having the centre stripe black. i cull on many things and often rely on randomness to get me closer to what i am chasing. sometimes i put a rooster in a breeding pen briefly before i cull him just to ensure diversity. if the chickens survive to adulthood then it is more luck. choosing the biggest and widest birds in my opinion would be very important. i would not choose a weak sickly bird because it excelled in lacing. if i chose a lesser typed bird then the mate would have to excel in type. the randomness i hope removes my inclination to bias to the detrimentl effect of the line. i always look at taking longer to breed what i want and know the line is stronger for it.