I have recorded C. guttatus, C. colletti, and Pseudechis porhyriacus in my 2000 paper. Since then I have seen it in both Darwin C. australis and "St George" C. australis. I have been told that the Wheatbelt W.A Kings and the Eyre Peninsular also do it. In all the cases the Males are larger than females in any Combating species...eg Oxyuranus, Austrelaps, Pseudonaja etc.
So my understanding from Richard's Size data I expected no combat to occur.