What a load of codswallop is being written here...
...In the UK...
Ah, well, there you go.
In the real world we just log what we fly, instead of padding our logbooks to reflect what really isn't.
Your logbook serves as a legal document, ensuring that you've met minimum requirements for licensing and certification, ensuring that you've met recency of experience requirements, and providing a way to track a record of proficiency. Logging all of one's time spent operating under an IFR clearance is a wonderful way to rack up IFR hours, but IFR hours are meaningless, and don't at all speak to one's ability or even experience at flying instruments.
If one makes a 9 hour oceanic trip in daylight visual conditions, one makes that trip perhaps with a brief climb through clouds on departure, and a brief descent and approach through obscuring phenomena on arrival...thus gaining .3 or .4 of instrument time. I can see where you'd be logging 9 hours of instrument time because the flight is done on an IFR flight plan with an IFR clearance. Good for you.
Around here we just call that padding your logbook.
You'll find that typically about 10% of one's time is instrument time. Some a little higher, depending on their vocation...if you're seeing higher percentages because you're logging all your time spent on a clearance as instrument time...do what makes you feel best. Paint little airplanes on the side of your cockpit if it makes you feel like an ace, and wear a silk scarf. At the end of the day all that's significant is whether you can do the job, and logging every waking moment as instrument time won't make you one iota more proficient, nor prove you so. As you will.