Is there a duty upon a stockbroker to ensure that the instructions are crystal clear before acting on the instructions?

In Smart v. Fowler Nathanson J., in founding liability in tort, held there was a duty upon a stockbroker in taking instructions to ensure that the instructions are crystal clear before acting on them, but he also concluded there was a parallel duty on a stockbroker’s customer to ensure the instructions he gives are equally clear. Liability was apportioned in that case as a result of a misunderstanding with respect to instructions which delayed the sale of the customer’s securities.

The reasoning of Nathanson J. in Smart v. Fowler is most persuasive and consequently I conclude that since the plaintiff failed to clearly and unequivocally communicate his intentions to the broker, and the broker failed to ensure that the instructions were perfectly clear before acting on them, then both were negligent and equally at fault for the loss sustained.