If discourse analysis demands an attention to the details of utterances, this does not mean that all such attention qualifies as satisfactory discourse analysis. Analyses provided by discursive, conversation and critical discourse analysts have, over the past twenty-five years, noticed and labelled a wide variety of conversational and rhetorical procedures. Anyone engaging in these sorts of analyses should properly acquaint himself or herself with such work. They should be able to recognize these conversational features in data extracts. The same is true of rhetorical tropes in printed persuasive materials and so on.
However, the recognition of features does not constitute analysis, at least at a research level. It may be appropriate in training exercises as one seeks to acquire the skills of analysis. But research does not, and should not, consist principally of feature-spotting, just as analysing the history and functions of the railway system cannot be accomplished by train-spotting. Thus there can be Under-Analysis through Spotting.
The interview extract contains many features known to conversation analysts. As the interviewer says mm or yeh they provide 'continuers' which acknowledge the respondent's turns. Thus by saying mm a speaker can concede their turn at transition-relevant points. Similarly when the interviewer asks a question, they are making the first move in an adjacency pair that expects an answer. These and other well-known structural features of the talk can be spotted in this extract. Indeed, such spotting is possible in virtually any such extract of interactional talk, just as the rhetorician will be able to spot familiar tropes in a piece of formal speech-making.
An analysis that consisted primarily of such spotting would not count as original research. It would be like a training exercise in running a well-known illusion such as the Müller-Lyer or administering a well-established personality test. Original analysis should seek to show how established discursive devices are used, in new sets of material, to manage the speakers' interactional business. What is required is to show what the feature does, how it is used, what it is used to do, how it is handled sequentially and rhetorically, and so on. To remark: 'that's a 3-part list' for example, is to identify a well-know discursive feature of talk and text; but the interest is in unpacking it and show what it's doing in this particular set of materials. Good analysis always moves convincingly back and forth between the general and the specific.