Martin (1992: 506):
(iv) Distinguishing genre and register makes it easier to account for differences between the sequential unfolding of text as process and the notion of activity associated with field. Depending on mode, texts may or may not unfold in the same sequence as the activities they accompany or discuss. Live commentary on a football match has a different structure to newspaper accounts of the game; the commentary starts at the beginning of the match, the news story with its result. The commentary and news story differ in staging, and therefore in genre; but they are alike in terms of field — they both reflect the sequence of activities which comprised the game. Unhooking field from staging makes it possible to show how texts of these kinds are alike and different at the same time.
 Martin's "distinguishing genre and register" translates into SFL theory as distinguishing text type and context (field tenor and mode), respectively. Text type is a point of content plane variation on the cline of instantiation; it is register viewed from the instance pole. Context is the culture as semiotic system, that is realised in language. In Martin's model, therefore, a point of content plane variation on the cline of instantiation is construed as a stratum that is realised by the culture as semiotic system. That is, language is realised by context — an inversion of the stratification hierarchy.
 This is already possible without "distinguishing genre and register". In SFL theory, context (field, tenor and mode) is realised in semantics. Similar fields are realised by similar ideational meanings; different modes are realised by different textual meanings, including different information flow patterns.