Section 11(1)(a) of the Act provides that, in a case of partial incapacity, the weekly payment of compensation shall in no case exceed the difference between "the weekly amount which the worker would probably have been earning as a worker but for the injury and had he continued to be employed in the same or some comparable employment" and "the average weekly amount he is earning, or is able to earn, in some suitable employment or business, after the injury". The appellant submits that, in a case such as the present where an injured worker has commenced, either alone or in partnership, to carry on a business in which he is actively working, the "average weekly amount he is earning" to which s. 11(1)(a) refers is the amount of the net earnings of the business discounted, "on appropriate evidence", to allow for factors such as the "earnings" of others and a return on invested capital. Judge Westcott refused to adopt that approach to the determination of actual or potential earnings in the present case. His Honour assessed compensation on the basis that the relevant "average weekly amount" was to be ascertained, for the purposes of s. 11(1)(a), by considering what services the worker actually performed in the business and what those services would have been worth if, instead of serving himself, he had been serving an employer or, put in another way, what he would have had to pay another for those services (Willis's Workmen's Compensation Acts, 37th ed. (1945), pp. 300-301).