All of this stuff used to go on a lot more often. My first promotion, 10+ years ago, the pinning of chevrons was so common that it was done to me right in front of the battalion formation (with civilian guests and all). At the time (I was 18) I thought it was cool, a right of passage, a sign of toughness.
When I was an NCO I wasn't a real zealot about these so called tradidtions, but I still thought banning them was indicative of some overall softening of mindset, as long as no one went overboard what was the harm right? after all aren't we fighting men? It seemed like it was "a Marine Corps thing, you wouldn't understand."
I was wrong though. The more experience I gain as a Marine, the more I don't understand pinning. I have been a Marine on active duty for 11 years, mostly in "frontline units". I have been in combat. Certainly any softening of Marines concerns me and I attempt to develop an inner toughness in my Marines. But all the outcry from the "Old Corps" about this issue being about an toughness and tradition was driven, I believe, from an overall aversion to change and does nothing to lend credit to the "tradition" of pinning. In fact pinning is just an excuse to pick on someone, and that is the opposite of tough.
So sure the advice on this issue can be to stay away for the sake of your career, or read such and such order, both of which are valid points. However, the real takeaway is if you remove yourself and take a rational man perspective on the issue pinning is just the wrong thing to do and just because it went on for a long time doesn't make it right.
(stepping off soapbox)