As stated above, I would NOT look at it as premium and regular comparison. But look at it as how cold is it now and what is it going to be.
Correct me if I'm wrong but 100% of #1 diesel is good till -40 degrees. #2 diesel is made a liitle colder than current temps.
So if current #2 is made till 0 degrees whether is treated or not. There is "Cold Vortex" (new terminolgy) coming with temps dipping down to -15. If you had or made a blend of 50/50 #1/#2 diesel it should be good for -20. You could blend down go whatever you need till -40. The kicker is finding out what the current #2 is, thats the variable.
Dyed diesel is only for consrtuction (ex bobcats) and farm equipment, OFF ROAD USE ONLY. I would use it if i could find it, less taxes = cheaper.