A320
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Confusion; Situational Awareness
No Specific Anomaly Occurred All Types
General None Reported / Taken
Aircraft; Chart Or Publication
I was surprised to learn that even in final approach and positive course guidance and on profile; the aircraft will fly a steady slope to the next restriction regardless of terrain and that you have to be on the entire approach segment.  This along with the fact we didn't alter the approach and followed the all users bulletin.  The bulletin gives a false sense of security that the coding will keep us clear of terrain since it says to comply with the all approach segments unless cleared differently by ATC- which we were cleared differently.  Regardless; we always have an obligation to see and avoid; especially in VMC.  Now that I know this thing will drive down to the ground; you can bet I won't be watching it to see how low it will go or what it will do going forward; regardless of ATC clearance.  My only recommendation is continued awareness for flight crews of the RNAV Visual approaches into Vegas and approach characteristics of the RNAV approaches in the airbus.  Also; I really think Vegas needs to not shortcut us on these RNAVs inbound.  Just creates too much hassle with automation and sequencing at times. Clear us to the initial approach fix and leave it at that until we call the field and are cleared for the visual approach.
Captain reported concern regarding visual RNAV approaches.