Dang. Simple and effective. Great idea! I don't know that I'd go to zero for the low end on yours though JimmyA. Maybe 6-12 if you are (aside from throat irritation) tolerating the current level well.
The reason I find it convenient to get 0mg and say 24mg is that it lets me cover all of the common strengths, and makes the math really easy (ratio of 24mg/0mg):
25/75 split: 6mg
50/50 split: 12mg
75/25 split: 18mg
If the low-nic juice is 12, I can't ever get below 12, and sometimes I really feel like chain-vaping something low nic.
But again, that's just me