Quote Originally Posted by Rafal Lukawiecki View Post

Unfortunately, this can also lead to some odd behaviours at extreme low grades, such as 00. See Nicholas Lindan short paper: "The Workings of Variable Contrast Papers and Local Gamma". For that reason, split-grade technique can be a little easier to use with filters a little harder, such as 1 and 5, rather than 00 and 5. I believe that is what Bob Carnie practices. The effect will be the same, but the observed changes will seem more logical when using 1 rather than 00 for certain mid-tones.
I believe Nichoas only found a significant flat spot in one paper type. I believe it was the warm tone.
Your logic is not correct. As soon as you add any magenta to the 00 you are no longer at 00, therefore the flat spot will not be evident. Using 1 instead of 00 to avoid the flat spot only makes sense if there is no magenta exposure.