Hey, be nice! We're not all like that!
Besides, the last five tests I took, I scored between 135 and 142 -
not that it means anything.
It's not our fault that we're smarter, tougher and prettier than
you lot! 
Okay, seriously, now.
Despite all of the uniformity imposed by military structure, a unit
is composed of individuals at the end of the day. The upshot of
this is that you will inevitably get you mixed bag of angels and
arseholes. Unfortunately, there is no preemptive way of weeding out
the arseholes - a problem has to be severe enough before
significant action can be taken.
A case in point would be two of the platoon sergeants in my company
- I will call them N and S for convenience. S was my platoon
sergeant, and I swear you will never find a more professional
soldier in any army. His level of preparation as a trainer was as
close to perfect as anything I have ever seen. He knew the minute
details of the subject matter, and he made sure we understood not
only what we were supposed to do and how we were supposed to do it,
but why as well. The result was a platoon that still ran like a
Swiss watch when plans went right out the window, as they are wont
to do after the first shot is fired. Not that things were entirely
problem-free, of course. As tripwire had pointed out, we do lack
some discipline, but in administrative matters. On the rare
occasion that something screwed up, S never raised his voice. He
would simply come into the barracks, shake his head in
disappointment and ask what we thought we were doing. The whole
platoon would trip over themselves backwards to set things
straight.
N, on the other hand, was the ultimate psychotic boy scout. He
would be running around, yapping like a Jack Russel on
amphetamines, terrorising his platoon. Nutcase that he was, I would
not be at all surprised if he was the instructor who drowned the
trainee - it sounds perfectly like him.
The funny thing about it was that N was ex-SOF, while S always
stayed in the battalion. My OC at the time was from SOF and was
performing his OC tour with my company. When the CSM was sent off
for his Warrant Officer's course, the OC had to pick a stand-in CSM
for an overseas exercise. Despite being non-SOF and being outranked
by N, S was selected to be the CSM, and as always, did a sterling
job of it - he was selected as the best CSM amongst the companies
that went for that exercise.
The impression I got was that the OC, being a man of good
judgement, would have entirely preferred not to have N in the
company. Wherever possible, the important jobs went to S instead
despite his being of lower rank, because he was more competent.
However, N was a lifer, and there was not much that could be done
about that.
On top of that, we once ended up in the same training area as some
of the SOF guys. N hung around with them, trying to look like one
of the boys, but they pretty much ignored him. However, they did
repeatedly approach S and ask him when he was going to join SOF,
and S had to keep saying that he was happy in the battalion. The
SOF boys preferred not to have N about as well, but unfortunately,
unlike units like the SAS, the selection process does not allow for
rejection on the grounds that the candidate will not fit in with
the units ethos.
The unfortunate bottom line is that I am not surprised at all that
something like this incident happened - with arseholes like N
running about, it was bound to happen at some point. Even more
unfortunate is the fact that nothing much could have been done
about it until it was too late.