"We see no basis for the suggestion that a 'part of a business' must be a discrete profit centre or that, to use the words of Hayman[17], 'the part must itself constitute a business'. Nothing in the Act imposes that limitation on the very general words used in s 149(1)(d). A benevolent construction of the word 'business' in the predecessor of s 149, without the express reference to 'part of a business', would treat part of a larger business that was itself a business as a 'business' within the meaning of the section. The words 'part of a business' mean something more. They denote a particular bundle of activities that constitute an identifiable portion of the total activities that constitute a business. Sometimes the part will be a discrete profit centre, sometimes it will not. That does not necessarily mean that everything done in the course of conducting a business is a 'part of a business'. … It is undoubtedly the case here that conduct of banking transactions with bank customers at specified premises and the functions engaged in by the employees themselves, were constituent, indeed 'core', functions of a bank. Further, both the volume of those transactions, it may readily be inferred, and the amount of work necessary to perform those functions were not insubstantial. There is no reason to think that the conduct of those transactions and the performance of those functions were not an apt and sufficient bundle of business activities to constitute 'part of a business'. But we disagree with the stipulation in Hayman that the part must itself constitute a business in the sense of being economically viable if conducted independently of any other commercial activity." (emphasis in original)