The torturing that goes on in Saudi to extract admissions is a known fact. They are not practising Sharia or any other kind of law there. They are a brutal Monarchy that are supported by the west for political reasons unfortunately .
You are so correct, the saudi version of 'shariah law' is perverse as it does not apply to everyone especially the dictator and his numerous family members. This regime which stifiles economic development by its mere existence is supported by the west whilst the taliban are labeled as bunch of scum bags! (didnt stop the US trying to make an oil pipeline deal with them back in the day)
This guy who is doing the executions, beleives he is doing his duty, its better that he is very astute at his work than sloppy.
In islam when some one is executed for murder for example and admits it and takes his punishement in this life, it means that in the hereafter his punishment will be reduced - in the executioners eyes he is doing them a favour, if u see my point.
Supermax prisons:
In the states i imagine rotting in a supermax prison is a worse fate than death, that is what i call cruel and unusual punishment. Imagine no contact with any human being ever again, no death to spare your mind while you go slowly insane, how can that be allowed? some things are worse much worse than death, its really quite horrible the level to which humans can stoop.