I saw this yesterday during a 16U AAU tourney.
A1 goes up to dunk, ball bounces straight up off rim,
but not too high. As the ball comes down & through
the basket A1 is still in contact with the rim.
Less than a second for the entire play. BI or not?

NF Interpretation
 

No, it's not. If the player carried the ball into the basket cylinder, 9-11 Exception allows him to touch the ball or goal without penalty. If he loses control of the ball prior to the ball entering the imaginary cylinder, and then grabbed the rim or touched the ball, it would be BI.

9.11.2b describes a similiar play and states, "The rules do allow a player to carry the ball into the cylinder above the ring or place the ball into the basket itself. It is basket interference; however, when a player touches the ball or the basket when the ball is in or on the basket, or touches the ball while any portion of the ball is touching the cylinder directly above the basket and the player did not carry the ball into the cylinder or basket."

I would like to see the play and determine if player on rim was gaining an advantage by hanging to remain in position to guide the ball into the basket. I have seen this done and called BI.

If he hangs on the rim to gain an advantage, that's an entirely different situation. I think Dan probably already knows the answer to that question. "In contact with the rim" doesn't necessarily mean hanging on the rim to gain an advantage.

Nah, definitely no advantage here. This was just your
typical 16-year-old-who-blows-1-out-of-3-dunk-attempts
almost blowing another. He had control going into the
cylinder & the basket, the ball just bounced around
the rim a few times, went up & back in. I kinda
suspect he didn't even know what had happened, he was
more concerned with making a safe landing. Opposing
coach had a stroke, poor guy, even the kid's own coach
had a sh*t-eating grin, like he just found $10.

Now that we're in AAU season, running into too many
well-meaning but poorly educated coaches, it's nice to
have this place to discuss these interestng cases with
folks who understand, and of course whenever I get a
compliment from Tony I put a red star on my calendar!

It would be nice if the "inexperienced" coaches took the time to come here and ask and learn. I have refereed in the past but think that every second I have spent on this group has been 100 percent worthwhile.

and then some!
 

DITTO!!!

100% Worthwhile
 

But its amazing how often I've mentioned this forum to a coach and he just looked at me like "Why would I want to do that?"