For Merit Badge counselors, it can be one adult and two or more scouts, and it can include the adult's own child. Or, it can be more than one adult with one child. I frequently held Merit Badge sessions in my living room, and my wife and kids were always around. Scoutmaster conferences can be out of earshot, but not out of sight. The rules apply to travel, also. I always made sure that the last kid in the car was my own.
When these rules were first implemented I went from feeling insulted, to just being amused. I got over all of that once I figured out that being a Scout Leader was a near-perfect set-up for a child molester (picture Alec Baldwin alone with a Scout in a tent).
I absolutely loathe people who use positions of authority to prey upon children, and I appreciate the BSA trying to keep those kinds of people away from from Scouts. The BSA works very hard to protect the children in its charge, and I'm willing to help.
I think the setup is overkill and is not a good example to make. It teaches that the least common denomenator is that an adult is a closet child molester. In the old days, folks certainly knew about them, and they were always properly demeaned. It is never a good thing to teach,or to imply in any way, that if one of your buddies dad's, or their freinds has a lone discussion with you about something, that their are, or that there is good cause to believe, that ulterior motives exist.
Those positions of authority can't be used for abuse, if there's clear and open condemnation and instruction given regarding molesting, at troop meetings at least. I see no reason to encourage and perpetrate suspicion regarding the motives and intent of adults in general. That doesn't foster the idea that adults are trustworthy, loyal, honorable, ect... It fosters the idea that know one is trustworthy, loyal and honorable, and they all need to be watched like a hawk.