Odd One,
The requirement for 800 hours of IFR time for an IRI, or 200 hours of IFR time to remove the No Applied Instrument restriction (see BEagle's post for the difference) is a JAR requirement, and is intended to refer to time on airways, navigating by following nav-aids with reference to airways charts.
The vast majority of the time spent on airways is not by sole reference to instruments, since you will generally try to get on top of any weather as quickly as possible. That is why time by sole reference to instruments is considered to be 4 times as valuable as flight under IFR.
The UK messes up this neat little idea by introducing the idea of following the rules of IFR flight when making what is basically a visual flight. So although, in the UK, it is entirely legal to fly around complying with the rules of IFR, but always clear of cloud, in sight of the surface, outside controlled airspace and navigating visually, I think it is clear that this is not the way the rule is intended to be interpreted, it's merely a UK anomoly. Personally, I only log time as IFR if I have actually planned a flight as an IFR flight, i.e. navigating by means of navaids (whether on airways or not), and I am prepared to enter IMC on the flight if I happen to encouter any weather.
FFF
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