I began to realize that this is a learned behaviour that people adapt into their worklplace, volunteer role and maybe even in social or family settings. Is it that they don't like authority? Why do they always question the process? Or do you take it personally when this person takes this alternate route of getting what they want done, their way?
Perhaps it would be worthwhile to sit down and have what has been termed a "fierce conversation" to nip this behaviour in it's early stages so both the person responsible and the superior can understand the layers beneath this type of behaviour. When you go deeper into the questions you can find the pattern of this behaviour and perhaps this person has a problem with authority figures or those that have been in leadership over their position.
I have noticed from the perspective from the outside looking in, that these people are sometimes viewed in high regard because their accomplishments show that they are great project managers. They get the job done! You may have to pick up dead bodies after they leave the project due to steam rolling over those around them but for those who only see the end result they are heroes. To me this is not a leader, this is more of a dictatorship and most people will not want to work with someone who never listens, or follows process, respects other's opinions or feelings. We all deserve to be respected and listened to. We don't have to all agree but instead sometimes come to the conclusion that we agree to disagree.
My recommendation as a coach would be to have that conversation before this person becomes
a source of irritation to you and to everyone else in the room. It is an investment that will provide long term benefits and prevent a lot of triage care down the road!.