I work as a UX designer for almost 2 years. And I think design in a transparent environment is really important.
Sometimes I think all the people in the team should know why the product is designed like this. Actually, the fact is just like that. Programers would like to tell you their thoughts about design even though their suggestions may be not appropriate at all. But if you don't explain the reasons, some parts of the product may be totally different from what you thought they would be. Because you can't explain all the things with the docs. There are always some points we miss.
So like the OP said, it's a good solution to build an open work environment where anyone can see what other members of the team are working on, including programers. You will get the feedback at the first time, and you will find it becomes simpler to explain the design to others in the team.
Sometimes I think all the people in the team should know why the product is designed like this. Actually, the fact is just like that. Programers would like to tell you their thoughts about design even though their suggestions may be not appropriate at all. But if you don't explain the reasons, some parts of the product may be totally different from what you thought they would be. Because you can't explain all the things with the docs. There are always some points we miss.
So like the OP said, it's a good solution to build an open work environment where anyone can see what other members of the team are working on, including programers. You will get the feedback at the first time, and you will find it becomes simpler to explain the design to others in the team.