I have been thinking about how to carry out my research, and have decided to identify what 'mainstream' advertising is precisely, since I cannot look at how adverts depart from it if I don't know what it is.
I have looked at a textbook in relation to the initial developments in advertising:
'British Television Advertising - The First 30 Years'
Edited by Brian Henry
Published by Century Benham Ltd 1986
AN EXTRACT:
" Between 1956 and 1959 expenditure on television advertising more than quadrupled, in the latter year exceeding the total revenue of all the national and London evening papers, which itself had just reached a record peak. It was not only the volume of television advertising but it's content and style, however, which captured public attention - the slogans, the jingles, the packs, the images, the straight captions, 'as advertisied on TV', familiar outside the home. This was 'marketing' as distinct from selling, and it involved trying to have on hand and to make available 'what the consumer wants'."