I am sticking with R-12 myself.

Could the time it takes to ' blow through'... increase the time in traffic on a hot day before the system starts to not cool the way it should ?

That is all I assumed for the doubling of the R/D ..... and perhaps the ability to change it out for moisture control without evacuating the system... ( with proper isolating valves )....

OK, I have the Delco R-4... so I am in better shape on this than a nippond compressor would be ?

Seems to me logically that the condenser is much more a bottleneck for efficiency or capacity than the evaporator... thus the quick reaction to an aux fan not working...

So I am going to put a parallel condenser in mine without changing the evaporator... which I would not have a clue how to manage in such a tight space anyway...