The lower the viscosity of a white: The better it performs at low temps.
---- You get that ink at working temp on an auto, and it becomes very runny. Typically losing the opacity you liked at lower temps.
The higher the viscosity of an ink: The poorer it performs at low temps.
--- You get that ink at working temp on an auto and it maintains a good viscosity for higher opacity prints I.e. a better looking white.
Can you make a lower visc white perform better at working temps? Absolutely, however, you are now creating a work around in order to MAKE that white ink work for you.
Depending on your shops parameters, working temps will vary from 80 degrees to 100 degrees.
Inks are tested in the Lab at approximately 72 degrees.
I know for myself, we try to keep our board temperatures at around 130 degrees when running. Lower if possible.
This keeps the working temps of my inks a bit lower than most shops I have been in.
I have not touched on inks becoming runny or getting gritty as that's a different discussion.