There seems to be many variables ( ambient temperature, humidity, in or out of direct sunlight among others) that could cause 'streaking' when attempting to dry a vehicle, either with or without a "drying aid".
As well, I have always been curious if the car wash media, and how much was left on a vehicle after what one feels is a thorough rinsing, had any impact on the 'streaking' issue.
For example: If one uses a car wash media that proclaims itself to be a "Wash & Wax" product....how much, if any, of a 'wax' product or other substances is lying on the wet paint's surfaces that could possibly interfere, or not be compatible/water soluble, with the "drying aid's" chemicals/ingredients.
Also, if a person has applied an LSP (wax, sealant, Coating) and it has had time to properly cure, I don't see it breaking down into a 'liquid' form, as it were, and ultimately interfering with the drying process, "drying-aided" or not.
Perhaps the use of drying towels that may have left-over products imbedded within could impart some 'streaking issues' also.
So many things to consider!
Just a few of my thoughts.
Bob
