I've just filled out your survey Delphine, but to some extent felt that the premise behind it was flawed. Virtually nobody but the authorities themselves use the top level EC regulations. Within the industry (defined as you will) we almost invariably use the next level regulations - CS standards, EU-ops, EASA-FCL, Annex II, and so-on and so-forth. Those you didn't mention, and are highly relevant to many of our jobs; we know that there are European Community acts behind them, but few people ever actually need to access those.
G