Shop I'm at has been doing this for years now.
A plastisol underbase has not been printed here in over 5 years. I was amazed at some of the techniques and ways they print 'off' colors.
The first time you put a dischare base on a purpleish-blue tri blend and see it flash to a weired red-brown color, your brain goes no way is that 109 yellow plastisol printed through a 200 going to be bright enough.. then it comes out of the dryer and your brain goes.. how the F did that work??!!