I did comment to Youtube also. IMHO blue and green V10 are totally different. I don´t like blue one because it is not "clean" like Pyro or green V10. So what i did seen from your results I think you might used blue?
I used the green Taom V10. I guess it is possible there could be slight variation from one batch to the next. The chalk I used is also a couple of years old, so maybe that is a factor too.