I've stumbled upon a long marketing post about better shaving techniques and instruments, which briefly mentions that "You should close your skin's pores after shaving by splashing your face with cold water", but it doesn't describe how it helps anything. The goal of that post was to sell some fancy shaving tools and not really educate people about how to care for their skin (face and the rest of the body). The post however mentioned that one should soak skin in warm water before shaving, so that would mean opening the pores, which even if just for easier shaving, would also result in some additional effects on skin.
So what does it matter if your skin's pores are open or closed? Do you have a better chance of keeping acne off your face either way? What if I like washing my face with warm water a few times a day? What if I live in a cold region where my skin cools off pretty fast? Are there any significant effects I should worry about?