Have you been involved in a situation where you had to confront a superior about their conduct?

Yes, the key is in presentation and if it's a matter of actions that could lead to a poor perception of the leader or illegal/ immoral behavior. Fortunately with the exception of one squad leader I had, the issues I dealt with were leaders actions that could cause them to be perceived poorly.

In all but two instances a private sideline conversation with the leader pointing out what was observed in a respectful but straight forward manner got good results. That's not to say things didn't get interesting and the info received in a happy coom- by- ah manner,(even the best of us, if honest, doesn't like to be told they are being an ass) but folks respect the truth and the worst they could do is fire me. As far as blow back to the troops goes, once shit was handled it was handled and a dead issue.

The one instance that the message wasn't delivered in a cordial manner, but still away from the troops, I was ready and more than willing to fall on the sword over as the individual had single handedly caused an absolute goat fuck that endangered the whole company. It was by the grace of god that we didn't loose anyone. I won't go deeper than that because they turned around and became a good leader and we get along well to this day.

The other instance where the actions pointed out, having not been corrected resulted in the loss of a great guy, another maimed and a couple folks going on to later commit suicide. Because an individual had too much pride to act on sound counsel. That individual was relieved and the incident is what led me to the you can fix it or you can fire me attitude. My battle buddy and I got medals for our actions before and after the incident but that doesn't bring back the dead.

If you see something that appears wrong bring it to folks attention, be polite , be professional, fix it . You'll sleep better at night.

That's actually a quite interesting question, fortuitously, in my case, no, though I did find it of genuine interest....

We're adults in a hierarchical system. If you have an issue, talk to the person. They either explain why it isn't an issue (to your satisfaction, resolving said situation), correct the issue (resolving said issue), or ignore you (or some variation, which allows you to escalate the issue to the next leader in the chain of command).

Retaliation for seeking guidance on a situation (as per above) is unethical and unprofessional, and one of reason we have Request Mast (and the other Service equivalents).

Just like we have a duty to investigate issues with our juniors, we have the same issue to investigate with our seniors. Communication and Tact is how we do that, since the relationship is inverted.

Something as simple as "I'm not tracking the logic on this decision. Can you help me out so I can make similar ones (according to your Command Intent/Command Guidance) in the future?" Keep in mind that most of our seniors have more experience at the next tier up, which changes the context of their decisions.

What may seem odd or detrimental to us, may actually be beneficial in the longer term either to morale or mission.

Well, I had a nice and private talk to the BN Co once about his actions that I felt were both wrong and inappropriate involving how and when to chew out a subordinate (not me, btw) and it turned out well. He was at heart a good and caring officer and actually knew I was correct when I pointed it out. Didn't stop him from flying of the handle completely, but he tended to keep that behavior with the senior people after that conversation. OTOH, I butted heads with the S-3 over instructions from his office to one of my people that was both illegal and unethical and he wasn't about to change it for Cpt. Cable, so that conversation went in front of a different BN Commander. He really didn't have much of a choice but to support me, but I didn't walk away from that one feeling like I made any friends.