Assume what you wish. It could have happened while he was present, and it could have happened while he was not personally present. His physical presence or lack thereof was not relevant to the investigation. He was held responsible, and was still disciplined. But hey, there are still 64,499 other cases to look at.
"He was relieved of duty because of specific mistakes and infractions that he personally committed."
That has not been proved.
"This is not an example of a man who gave perfect orders and did his duty to the utmost being dismissed because of actions undertaken by others on their own initiative."
There are no requirements in the Navy to issue "perfect orders."
"The US military does not convict or punish people for other people's crimes."
Yes it does. It is called "dereliction of duty." General Karpinski at Abu Grahib is an example. There are many others. All one has to do is search, that is, if one wishes to put forth the effort.
"Again, I find it personally offensive that you accuse the US military of deliberately committing grave miscarriages of justice against its own officer corps. You don't have a stitch of evidence to substantiate the charge."
Well, you need to take that up with the military. Officers have been disciplined a lot over the years for things they did not authorize, cause, or participate in.
COs don't usually plan vacation time during maneuvers.
Ultimately, it's an immaterial distinction.
If he wasn't present to direct maneuvers that's an obvious strike against him for doing a poor job as a CO for not even showing up. If he was present to direct maneuvers and directed his vesel aground, that's also an example of Henderson personally doing a bad job.
That has not been proved.
The article itself states that he failed to report the unseaworthiness of his vessel for at least two weeks. That's unacceptable and that's entirely his fault.
It is called "dereliction of duty."
Dereliction of duty is a specific offense committed by the accused, not by someone other than the accused.
Dereliction of duty is just what it says - the accused failed to do the things they were personally obligated to do.
If you are not doing your job it is not someone else's fault - it is your fault.
Karpinski's job was to make sure that protocols were being followed, while it is clear that she was not even bothering to do the most rudimentary evaluations of her subordinates' performance. She herself personally failed to do the things she was supposed to do.
Officers have been disciplined a lot over the years for things they did not authorize, cause, or participate in.
Yet even a single documented example of such an occurrence seems to be quite elusive.