My contractor and his painter used Sherwin Williams ProMar 200 Flat directly on new drywall AS a primer in a bedroom. I didn't catch it until it was too late. They say they have good luck with this approach. I saw a post on this forum from 2007 where respondents emphasized that primer is needed because flat paint will absorb the top coat, making the result splotchy or streaky. The difference in my case could be that they got the SW ProMar in the exact color that we are going to use for our finish coats.

I'm wondering, now that we have a "base" coat that's all one product (even if it's not primer) and it's been tinted to match the finish coat exactly, how much of a problem would this be? I know it would be safer to use primer, but anyone have any experience with this approach? We are planning to use SW Duration as the finish coat.

Thanks!