Clarify the relevant secondary sources and responses

‘Clarify the relevant secondary sources and responses’ involves identifying secondary sources and responses and documenting what is involved where this is worth while in clarity efficiency terms. The extent to which it is worth identifying and documenting secondary sources and responses, including any relevant tertiary and further higher order levels of sources and responses, is very much a matter of judgement, necessarily dependent on a variety of issues. Once again, the key lies in keeping the analysis as simple as possible without overlooking any important issues. Further consideration of wet buckles illustrates this point.

If ‘repair’ becomes the primary response to a pipe buckle, an important secondary source involves the ‘pig’ that is sent through the pipe to dewater it, as it may run over a boulder or other debris in the pipe and become stuck. Pig technology is now well developed to clean and inspect pipelines, and modern ‘pigs’ have closed circuit TV and computers on board, but with or without this kind of technology, a ‘stuck pig’ is a serious problem. Despite the chuckles it may evoke, it illustrates a secondary source of uncertainty that needs careful attention.