First of all in training we create a situation where the AR is nonfunctional. That is the reason for transitioning in the first place. As Jon mentioned, one should only go to the handgun as a secondary weapon when deploying the AR in this type situation. Moral of the story, we do not drop the ARs into the slinged position when transitioning if it is capable of firing another round and to do so would be a gamble with safety! And even with the weapon incapable of firing we instruct that the muzzle should never sweep the operator's body or sweep other individuals present. If the sling is incapable of accomplishing this safe task the weapon and sling are not permitted to be used. Or must be adjusted so it will comply! We have instructed this LE drill for some 20+ years at the Academy and not once have we had an issue with this exercise. Safety is always the number one focus when doing any firearms training. When they are not on the line actively participation in actual live fire exercises on the firing line the Yellow Safety Blocks are in the Magazine Wells at all times on the Range and in the classroom.
The Constitution is not an instrument for the Government to restrain the people. It is an instrument for the people to restrain the Government!
Today, we need a nation of Minutemen, citizens who are not only prepared to take arms, but citizens who regard the preservation of freedom as the basic purpose of their daily life and who are willing to consciously work and sacrifice for that freedom."
-- John F. Kennedy