Third, it is not clear to me that Intruder yet comprehends that not all procedures everywhere are the same. Not even in adjacent countries in Europe.
If I didn't comprehend, I wouldn't have cited the VERY RECENTLY CHANGED differences in arrival procedure differences in the US and UK.
However, NOBODY here, including the French ATC, has offered ANY evidence that a descent below the already-cleared altitude/level is allowed on a direct-to clearance PRIOR TO the IAF. The exception for "cleared for approach" in Canada cited above is interesting, though I suspect it is used more in remote locations than as a routine procedure for airline operations into major airports.
If you have citations to show otherwise, please post them!