I never have done it but we have a lot of shops that stock all three color and will change colors as they apply it.
Might as an example put a coat of black and then two coats of gray or white for first blocking.
Got some turbo primer several months back and used it on a few hail damage repairs and so far its great. Now I'm comparing it to what I was using which was p30 primer, even though its not quite as fast its fast enough for me. The p30 is way over priced and its kinda gummy to me. Thanks for a product that's not only a great price but also fills good and sand really great, Now maybe you could make it a little shinier.