I wouldn't have thought so.
To be honest even when I went through the system years ago very experenced FAA twin IR pilots some of them CFII's did have quite a few issues with the JAR IR.
It didn't really come from lack of scan etc more of having to relearn something requiring a prescribed procedure for the test.
The stalling was different to what they had been taught. ie no powering out reduce AoA then apply power.
NDB work was ropey.
Altimeter work was quite often forgotten.
RT was utter !!!!e.
They were quite lost without GPS as it was an intergral part of their scan.
Holds, there was a difference there which seemed to cause no amount of grief.
When the work load got up they reverted back to FAA practises.
But that is only from the 3-4 that were at the school at the time.