Uh, not in this case. These aren't subtle blend problems I'm talking about. Think of a loud-playing 6th grader playing everything blastissimo in a good high school band. Scary actually.I read about a tenor player whose community band director criticized his choice of a link STM. He was emphatic about it. Too harsh. Didn't blend. Cut through everything.
At the next rehearsal the tenor player had the link carefully dressed in black electrical tape. The director commented on how much better the blend sounded.
Sometimes these guys hear with their eyes.
The first step is to get them to listen and to do that they have to play softer. Not by a lot but enough so that they realize they have no air support. If we were talking semi-pros, the ask is much less or not worth pursuing.