Oz,
Although it's not written down explicitly anywhere, I don't think that is the way the UK rules are intended to be interpreted.
The basis for me saying this is purely down to the requirements for teaching instrument flying, where it is made clear that time can either be logged as "IFR", or "by sole reference to instruments". The fact that time "by sole reference to instruments" is more valuable than "IFR" by a factor of 4 is enough to convince me that it is quite permissable to log "IFR" under circumstances such as when flying in VMC on an IFR flight plan - very different to the way you describe the rules down under.
FFF
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