I wouldn’t do it if it’s not required. Pressure washing forces water into every small crack and cranny, and if it doesn’t get completely dry before painting, you can end up with your paint blistering in spots. Problem is, you won’t know if there is still water that hasn’t evaporated yet until that happens. I’ll also put in a vote for the Sherwinn-Williams product.
That used to be true, but most decent water-borne paints are “breathable” now and allow for moisture to escape from the substrate through the new coatings. If this wasn’t the case, it would simply be impossible to properly apply coatings to any surface in a very humid climate.
Modern paints simply don’t blister like they used to. In fact on very porous surfaces, it’s a good idea to lightly dampen the substrate before painting. On hot dry days, it’s been common practice for me to damp down porous wood and masonry prior to the first coat. The new coat is “pulled in” to the substrate and adheres tight as it dries. A completely tight and dry surface has less tooth for the new coating and is actually more likely to fail prematurely.