A black x split will give you 50% black and 50% Split and you won't know which is which.
I believe you make the quickest improvement by breeding split x split. You only get 25% Lav chicks and the blacks that hatch are an unknown and I cull them, but you bring in a higher concentration of the "black" genes with this approach.
If you want to improve your stock use this method. If you are in a hurry to produce the maximum number of lavs to sell, breed lav x lav. If you fall somewhere in between then Split x lav would be your option.
Ah, thank you - I had my math mixed up.
I guess my approach will depend on what birds I end up with. I would prefer to use any bird with good type, black or lavender. I don't like knowing if the blacks are splits or not, that's why I chose lav x split crosses. At least there all of the black ones are splits.
Is there any "recommended" cross to test for lav genes on a black possible split? Or do you just cross with a Lav and see if all the babies are black - which would mean (assuming you hatched out at least a dozen) that it is not a split. This is in case I have to re-think my breeding program due to lack of good stock in my color choices...