> if the shy person is new
> if the issue is that the person is afraid to speak up
But that's my whole point: it's not always "fear". I'm talking about character. Personal preference. Or "people/character colors" or "16 personalities" or some other names it had.
Enforcing a strict way to communicate and bashing exceptions (which is my way of phrasing the original comment) will work for some, but will also create an artificial leash for others. I think it's too strict and to generic to try to just implement it by force. Yes, whole team should be available to see details, be able to participate, but why enforce that on such a low level as forbidding 1:1 talks...
From my recent experience, aside of excluding many personalities, it kills a lot of inertia that spontaneous prototyping and brain storming needs.