“O-6 of one service sentences O-7 of a different service.”
There is a difference between rank and authority.
Absolutely, and not all that uncommon. A Captain bomber pilot may have a major and/or LtCol navigators as part of his crew. In the air, the pilot is boss. Same where a military hospital commander by law had to be a doctor, but there were nurses who were higher ranking. The doc was still the boss. Same with the courts. It’s still the judge’s court.