How Should We Define a Vague Grade?

Here is a floor I looked at where the client selected a rustic-style floor that only had a generalized grade. After installation, the client did not like some of the planks, including one in the photo at right. Can you guess which one it is?

They were concerned about getting slivers when walking on the floor barefoot (and I can’t blame them). In the first photo you can see a larger view of the room, which shows how the board fits into the grade, and below that is an expanded view showing the detail of the board. Which leads me to ask: From an installer’s point of view, when the grade is this low, how are you to “inspect” the floor prior to installation? When a client is shopping for a “rustic” grade, where is the cutoff on just how rustic we get?