I believe what you're saying here is just a rule clarification - but an "incorrect" building placement would generate an alarm(!) by the game no?
What I was getting at (that I saw in another post) was this:
Say that you have a Mill within range of a Bakery (the Baker can pick up Flour from the Mill) and say that this same Mill is also within range of a Market (the Market cart can also pick up Flour from the Mill). If both Market and Baker send out a Cart/Journeyman while there's still Flour at that Mill, one of them will get there first and take all the Flour- the other one will end up travelling a long distance for nothing.
So I'm saying that there can be "contention" for a Production building's goods. You might also see this with multiple Markets servicing one building (i.e. both send out a cart at the same time but only one of them collects any goods).
That's why I suggested to keep the Bakeries away from the Mills. If you do this, the Baker will always go to the Market which should always be supplied with Flour so no trip is ever potentially wasted.