I would suggest that you learn to walk before you run. I don't mean that to sound patronising but I feel you would be far better racing your youngsters naturally for a couple of years just to get to know your birds and their habbits first. Once youv'e done that, then if you still want to have a go at the darkness system then I would suggest that you read as much as you can on the subject, visit as many top flyers using this system as you can. Then work out your own plan of attack and stick to it, because what works for one man dosen't always work for everyone. All the best with whatever you choose to do.