It's too far to backtrack in this long thread to find the author of "unnecessarily risky and doesn't have a prudent margin for error" so I apologise for the lack of attribution but I think this a fair summary of what in my view was damn poor airmanship. If he was the Chief Pilot, he should be taking tea and biscuits with himself.
It has been mentioned that one of the "permitting" factors was the ideal weather. Did whoever said this see the videos? Quite a bit of thermal activity suggested by the cloud development to be seen there, don't you think?
Regardless of the terrain, trigonometrics or any other attendant consideration, the fact that so many have responded to the poll in a manner critical of the seemingly reckless behaviour of the PF suggests that any public relations benefits flowing from the TAP/Airbus display were negated by the actions of the display pilot. This demonstration might have had the ghouls and thrill-seekers on their toes but it did nothing to instill public confidence in this particular carrier nor the professionalism of those to whom it entrusts the safety of its aircraft and PAX.
GQ.