The LNAV plus V is a staggering safety improvement because you monitor what the aircraft is doing.
I didn't say it wasn't. I merely pointed out that it is not what you think it is, and there are other things you need to monitor when using it.
With the Garmin LNAV plus V I am referring to there is no barometric input. It takes the height from the GPS.
If it is using un augmented GPS height then it could be out by more than a baro correction. GPS height is referenced the WGS84 geoid and in Aus it is about one hundred meters below amsl in Perth and about the same above in QLD.