So from what is being said on here, many (most?) approaches cannot be flown as coded because they will invariably have a level decel built into the profile at an altitude other than your ATC cleared level..(Airbus). I must/ should either modify the FMC to ensure it descends to the ATC level first, or select a mode giving a minimum of 500fpm descent to that point?
All approaches have FAF altitude or platform altitude. Generally the clearance is given to that altitude. Sometimes when the clearance is below that you should descend to that after confirming.The approach profile can be intercepted below FAF altitude without modification. In case of managed NPA it's not permitted to modify the FAF altitude.