I'm surprised that no one has so far mentioned the requirements for instructing for an IR, since these, IMHO, give interesting clues as to how to log instrument time.
In order to instruct for an IR, you need a certain amount of IFR flight. The rules then go on to say something along the lines of (I don't have the exact quote to hand, and I'm not going to track it down right now because the exact details aren't relevant) "if you have logged time by sole reference to instruments, as oposed to logging IFR time, then 1 hour by sole reference to instruments counts as 4 hours IFR."
There are a few points here:
First of all, there are (at least) two different ways of logging instrument time.
Secondly, an hour by sole reference to instruments is considered more valuable than an hour IFR. From that, we can surely imply that you should log your time as IFR, even if you are in VMC and not using any view-limiting device, any time you undertake an IFR flight - this is why such time is not as valuable as time by sole reference to instruments. That would include any airways flight. It would include any flight where you are prepared to enter IMC should you encounter such conditions. It would even include any night flight in the UK outside controlled airspace - although that may be stretching the point too far!
The alternative method of logging time - by sole reference to instruments - seems to me to only include that time where you are in actual IMC, or where you are using a view-limiting device.
How does this relate to an IMC instructor? Well, if the instructor has chosen to log his IFR time, then any routes he flies, and probably any approaches, must be IFR, and should be logged as such. General handling might be IFR, or it might be VFR if the weather is VMC and the instructor has chosen to fly VFR.
On the other hand, if the instructor has chosen to log his time by sole reference to instruments, then only that time in actual IMC may be logged, since the instructor is presumably not wearing a view limiting device.
So, is this actually relevant? It is based purely on the requirements for becoming and IR instructor, which is something which no one has asked about, so maybe it's not relevant? But, as far as I'm aware, there are only 2 times where either the CAA or JAR-FCL requires a given amount of instrument time. One is the instrument flying requirements for ATPL issue (75 hours, I think?), and there is no detail about exactly what counts as instrument flying for this purpose. And then there are the requirements for becoming an IR instructor. So yes, I think it is relevant, because it's the only written guidelines that I can find anywhere.
All of this assumes, by the way, that BEagle is incorrect in his assumption that an IMC instructor can not log instrument time because he is not at the controls - something which everyone seems to be agreed on except BEagle himself.
FFF
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