Paul
This is adequately covered in the Working Time Directive
Oh no it's not, The working time directive has holes big enough to drive double decker buses through when it comes to on-call etc.
For instance nowhere is "compensatory rest" defined and this has not been defined in any of the test cases brought to court since it was instigated.
The WTD examples quote that compensatory rest can be taken as part of the weekend after the statutory 35 hour break, which implies that compensatory rest does not have to be paid. Many employers are now no longer paying periods of compensatory rest.
In short until a test case is taken out on these specific issues no-one is sure where they stand, and the area is so grey that no-one wants to take out a case incase it goes against them.
The only plus point at the moment is in the small print of the "Jaeger" judgement, where the presiding Judge stated that employers should "encourage" workers to take compensatory rest as soon as possible, and non-payment is definitely not encouragement!
Paul (Hope this doesn't sound too trite

I've spent many many hours trying to pin down "compensatory rest"

)