Originally Posted by
alcjphil
This means that if you use these chinrings you would not normally have more than 1 chainring and you would not have a front derailleur
Exactly. Thanks for stating it more clearly. These chain rings are designed to hold on to a chain even when you're bumping around off road.
So you would never want to run one on a crankset with two or three chainrings. All modern chainrings designed to be used with front derailleurs have teeth profiles that allow the chain to "fall off" more easily so it can be shifted to the other chain ring.