The level off thing, or dive and drive, however you wanna call it, is not allowed anymore for AOC-holders under JAR-rules. You have to fly a continues descent final approach to MDA or nowadays DA and execute a go-around if not visual by then.
By the way, Boeings 737 FMC-update 10.8 actually tried that, it flew 200ft low under certain circumstances on NPAs and they had to re-call that update ASAP as that behaviour (and some other snags) were deemed dangerously unsafe.