Martin & Rose (2007: 134):
And there are other common items that are used to add a ‘sidetrack’ to the flow of discourse — anyway, anyhow, incidentally, by the way. Here’s a couple of examples from an anecdote about language teaching and language knowledge:
A teacher was confused about which of affect and effect was the noun or verb (it's affect verb, effect noun by the way, except for one formal meaning of effect 'succeed in causing to happen'), or was perhaps unable to recognise the noun or verb in the sentence he was policing. He marked the student wrong, suggesting affect for effect or vice versa (I can't recall which). Anyhow, as it turned out, the student had been right; the teacher got it wrong. (Martin (2000), Grammar meets Genre).
Blogger Comments:
Here Martin & Rose misconstrue two distinct subclasses of elaboration — dismissive (anyway) and distractive (incidentally, by the way) clarification — as one subclass of extension (addition), and rebrand Halliday's textual grammatical system (cohesive conjunction) as Martin's logical discourse semantic system. Halliday & Matthiessen (2014: 613):