That's how it should be ideally, but that can be a problem depending on the infrastructure around you. In my area (South Jersey) the design speed of our roads is consistently much higher than the posted speed limit. This leads to a lot of people consistently going much faster than the posted limit, and to people internalizing the idea that e.g. it's only really speeding if you're going 10+ mph over the limit. Which isn't actually safe in a lot of places!

If the design speed of your roads is a safe speed for those around you then yeah that works perfectly.