Will Branson still have a 51% controlling share? If so I wouldn't want to buy SQ's ahare. If Air France KLM bought out some of Branson's share so that DL/AF/KL had a controling share it could be very interesting.
He appears to have got past two checks, firstly by airport staff who allowed him airside and secondly by handling agent staff who actually let him onto the aircraft. Chances are both thought that he was the son of an adjacent adult and didn't ask for further identification.
The UK does not generally check the passports of outbound passengers although they have the right to.
The gate agent should always check the passport of passengers of only to avoid a fine at the other end. (This only applies because the UK is outside the Schengen area and would not be true for most intra European flights.)
Barrier checks such as LH uses at FRA and at LGW outbound should be foolproof unless of course someone takes someone else's boarding pass or "jump" the gate.
Boarding procedures may be better a picking up passengers who have not boarded than those who have boarded without a BP. (It goes back to the days of baggage reconciliation.)
As Blogger Bob says it it is only one layer. No single layer can be infallable (I've forgotton to take my bag of liquids out and its not been picked up). Luckily there are multiple layers.
I certainly would't want highly intrusive Israeli security with check in 3 hrs beforehand.
As far as profiling is concerned - then the hijacker tries to find a wiling person with the right profile - or in the case of a thrawted attempt to place a bomb on an El Al jet at LHR a few years ago a girlfriend with the right profile.
Not strictly security, but closely related, the has been a fus in the UK about full checks not being done for all arrivals at immigrations. Also certainly it would have been whites from low risk countries (Australia, Canada, US etc) who were "waved through" which is effectively profiling. Well if that causes a fuss what would security profiling cause?