Misrepresenting Tenor As A 'Register Variable'

Martin (1992: 403):

NEGOTIATION is realised through the interpersonal grammatical systems of MOOD (alongside MODALIZATION, MODULATION and ATTITUDE); taking interpersonal metaphor into account, these systems are all strongly correlated with the register variable tenor.

Blogger Comments:

[1] Realisation statements specifying how negotiation is realised in these grammatical systems are not provided.

[2] This is irrelevant to the point being made.  Realisational relations across strata hold even when not "taking interpersonal metaphor into account".  Interpersonal metaphor is the incongruent varying of such interstratal relations.

[3] In SFL theory, the realisation of the contextual system of tenor in interpersonal meaning and wording varies according to register. 

[4] In SFL theory, tenor is the system that models the interpersonal potential of context.  It is not a "register variable" in the sense of being a system of register because register is a functional variety of language, whereas context is a semiotic system that is more abstract than language.