‘Goldwater’ operates a beer brewery and ‘Carryon’ operates a road haulage company. The two companies enter into a contract in January 2012 in terms of which Carryon agrees to transport Goldwater’s beer to a wholesale depot located 50 kilometres away. Clause 8 of the contract governs the collection of the beer by Carryon. It provides: ‘Goldwater will make the beer available to Carryon at the brewery premises located at [details of the address].’ In February, Carryon‘s driver arrives at the brewery and finds that the crates of beer that he is to collect are located on the fourth floor of the brewery. He will be unable, without assistance, to move the crates to the ground floor and load them on to the haulage vehicle. When he asks for assistance, he is told that none is available due to redundancies at the brewery. Carryon's driver leaves the brewery without collecting the beer. Carryon refuses to perform, arguing that Goldwater should have made the crates available at the front entrance of the brewery. Goldwater disagrees. It made the beer available at its premises, as was agreed in Clause 8 of the contract. It, therefore, raises an action against Carryon for breach of contract. Carryon disagrees with Goldwater's reading of Clause 8. It argues that Goldwater and Carryon have an ongoing business relationship and that under every previous contract between them, Goldwater consistently made the crates of beer available at the front entrance of the brewery. Clause 8, Carryon concludes, must be understood in the light of these facts.

Assume that the previous contracts between Goldwater and Carryon were identical in all significant respects. Also assume that the contract does not specify on which floor the crates are to be collected and that there is no local trade custom relevant to the matter at hand. To what extent may the manner of performance of the previous contracts between Carryon and Goldwater be given weight in the interpretation of Clause 8 of the 2010 contract?