I find dealing with the same sawyer all the time helps. Understanding his limits helps too. For example, if at all possible we design our buildings to use 16' or shorter stock. We do this because we know the sawyer often gets his logs delivered at 16' instead of full length. It is also trouble for him to get anything longer than 20' into the mill. Sometimes we up the size of rafters not because we need it structurally but we know locally they will come from a more stable timber.