So I'm painting this door black and I wanted waterbased Satin Impervo but the guys at the Ben Moore store said they couldn't mix black in the acrylic formula, only in the oil. I bought the oil. This is my first time painting with alkyd paint.

My question is, why does the can say DO NOT THIN? There's no way my sprayer is going to handle this stuff unthinned. The Internet at large seems to feel that mineral spirits are a fine thinner, in general; can I use those?

Thanks.