Without a two tank system, you are going to have cold thick oil splashing into a cold engine when you start it, which has been argued will lead to incomplete combustion of that oil. What happens to that unburnt fuel is debateable, but it has been suggested that coking and gumming could occur as a result.
I like having BD in my IP and injectors when I start cold, so whatever may happen in the former scenario is not my concern.
I cold filter my oil, takes a long time, but for a guy who uses 5 gallons a week or less, small potatos. If you cold filter, the oil will never solidify, anywhere in the system, provided to don't drive to colder climes.
Heating the tank, the lines to the engine compartment, mega-heating the oil b4 the IP with the fore-mentioned Vegtherm, and switching to BD for shutdown cover all the angles, imo.

The only two wise ways to do single tank imo are:
1. swapping injectors made for thick oil spray pattern, or blends. I don't want to swap the injectors to those designed for oil because then you shouldn't run regular diesel through them for any length of time, and I like to travel.
2. blends. I will not do this because a huge reason for geting on oil for me, is to get off petroleum amap. Some blend people are using 15-30% gasoline. Doesn't sound too environmentally sound to me.

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