Thanks danger, it is a fair comment (the same could be said of LHR-MAN), however as I'm already 4 segments short of the maximum of 16, and I believe that the Australian flights count by themselves as a separate continent, these short trips only cost me the taxes... I suppose the ideal scenario would be to do HND-SYD, SYD-OOL, OOL-MEL, MEL-PER, PER-HKG ... then I'd have to call Qantas to book rather than use the tool due to that PER-HKG refusing to show availability on the oneworld tool (I think this is within the rules right as still only 4 flights in Australia)?
(There is a reason to do SYD before MEL that involves seeing certain friends on Christmas day)

Note: In the time between posting I've realised I can do a LAX-JFK, LGA-ORD-LHR add-on trip to Chicago that may maximise it (pointless land segment, but LGA is going to be far easier to get to than JFK I guess.. I could do JFK-ORD as well), and I'd rather have a 10 hour flight than a 6 hour one.... though again the tool is misbehaving and not showing me the AA day flight that has D7 availability, only the overnight BA ones.

Edit: If ringing up, you think I could persuade the Qantas agent to book me onto the BA codeshares rather than the direct AA flights btw for all these American ones? Would help me maintain my 4 segment status for gold with BA! In fact... where would I ideally book, will anyone let me book and pay in HKD to avoid the currency surcharge of 2% on my credit card... I guess it is a choice between Qantas (first flight), British Airways (to get my codeshares) or Cathay Pacific (for HKD charging... but at the moment their call centre is shockingly slow)?