Yeah, I always split my stacks up before posting them up for sale, stacks of 10 on average. They tend to sell pretty quickly out of all the things I post, which says something (I price in the average so it's not the pricing). The only time posting just 1 is a good idea is when it's the only idea, like with equipment and special items as the Wanderer's loot. There are times I do post whole stacks of 99, but it's usually things like pigment or logs where it's not the end product or doesn't craft evenly, but that's rare.