There's plenty of room to add a simple warning: [FONT="Arial Narrow"]Attention - incorrect use of this option causes routing problems[/FONT]:
That may not be the best, but something pithy that alerts the admin to the fact that this option is not for neophytes!
If I had my druthers, I would add a context-sensitive help here labeled More information and that would include a full explanation, including the limited cases for use of the option. The help also would have suggestions for alternatives; for example, for creating an 'Additional Address' and then using the "Interface [Additional] (Address)" object created by WebAdmin instead of a Host definition bound to an interface.
Cheers - Bob