There is no sensible reason why an FAA IR should not convert to a EASA IR
We need to stop using words like "sensible".
Sense is not the driving force and sense is very unlikely to win the day.
EASA have a wholly different agenda.
Beagle
Validation is an interesting point.
My problem is with a scientific background I like evidence to support legislative change - rather than it seeming a good idea.
You will recall there was no validation for the VFR rating, then there was validation by C of E, and then by a flight with an instructor maybe one day there will be a compulsory flight test. The point being I am not aware of any evidence this has made things safer. There may be evidence, but I am not aware of it.
With regards the IR the FAA have done things their way for as long as I can remember - is there any evidence that changing to an annual test will make things safer?
If there is any justification I suspect much of this is directed at the rare exceptions. I think most pilots do a pretty good job of policing themselves - there is the odd individual who think their skill levels are better than they are, or perhaps are self deceivers, and just maybe re-validation does prevent these individuals killing themselves.
Perhaps my "problem" is making an exception for instrument flight. Also it is an interesting dichotomy that the FAA require a compulsory VFR test every two years, but self validation for IR privileges, whereas we require no basic test of a pilot's flight skills but we test IR privileges.
As I said earlier - "sense" doesn't come into it.