We all know LtEve had Harry not been a Royal it is highly unlikely he would have got to Sandhurst
Not true Littlemiss. He was borderline, as are numerous other potential officers. He did fantastically well at Pre-RCB/RCB and that secured his place.
Lots of POTs get to RMAS that way, and then have to prove themselves. He proved himself in spades, and whilst they considered he would not have been able to join a 'Techincal' Corps or Trade, he was eminently suited to a Combat Arm, which is what he joined.
He then did his training with AAC, and came top in many of his technical exams, so again proved his knockers wrong.
The Army would lose a lot of potentially excellent fighting men and women if they relied solely on examinations and qualifications. The very best Officer I know, the 'only' one that I would follow blindly into battle hasn't a formal qualification to his name, but his tactical knowledge, experience and ability is quite simply outstanding.
Conversely, the worst officer I ever knew had a bundle of completely useless examinations and a degree in something like "Ancient French" He was a technical officer, a liability and quite simply a danger to everyone! Thankfully he was found out before he could do any damge 