In West India voyages, crews are often thinned greatly by death and desertion; and if a promise of advanced wages were valid, exorbitant claims would be set up on all such occasions.

72, where that learned Judge held, that no action would lie at the suit of a sailor on a promise of a captain to pay him extra wages, in consideration of his doing more than the ordinary share of duty in navigating the ship; and his Lordship said, that if such a promise could be enforced, sailors would in many cases suffer a ship to sink unless the captain would accede to any extravagant demand they might think proper to make.

[3]The lawyers for the plaintiff attempted to distinguish this case from Harris v Watson by pointing out that the circumstances were completely different, and that the captain had offered the extra money without any pressure being brought to bear by the crewmen.

But the desertion of a part of the crew is to be considered an emergency of the voyage as much as their death; and those who remain are bound by the terms of their original contract to exert themselves to the utmost to bring the ship in safety to her destined port.

[7] The practical benefit doctrine has recently been extended to a lease agreement which involved the payer of a lesser sum in MWB v Rock Advertising [2016] EWCA Civ 553 which has led to considerable criticism.