In these examples, I have made it fairly clear that I would prioritize the pedagogical argument, and why. Here is a third example, where I would not. Frequency studies again. It has been shown that the present progressive tense is far less frequent than the present simple (Duskanova and Urbanova, 1967; or you can test this out for yourself by taking a random selection of written and spoken texts and counting!). But the present progressive is far more ‘teachable’: its structure does not entail the difficult do/does interrogative and negative forms, and its meaning can be easily demonstrated in the classroom and lends itself to interesting mime – and picture-based practice. The temptation is to teach the present progressive first, and to spent more time on it – a temptation, I think, which should be resisted.
In other words, when deciding what to teach and how to put it across, I have to consider both linguistic and pedagogical arguments, and then decide which has the priority, or how to combine them. In deciding, I need to use all the knowledge I have gained about TEFL through courses, experience, reading, discussion and reflection.