... If I were an AoL AS, I would design the Binder to work as you suggested, not as Sidious suggested. Then it could be used on any channeler of any age.

Plus, I can't really think of any reason why RJ would have wanted it to work like Sidious suggested. All it does is limit who could be Bound with it, so it would eliminate old channelers, like the Kin, from being candidates. That's it, really.

But, it seems Egwene's idea now is for AS to continue to swear the 3 oaths when they are first raised, and then unswear the oaths when they are ready to retire, so that they can live out their allotted, unbound lifespans. That assumes, though, that when an AS unswears the oaths, her lifespan reverts back to what it would have been had she never sworn them in the first place.

But that's something else I've wondered about. One possibility I've considered is that, when oath-bound, a channeler ages at (say) 2X the rate she would if not oath-bound, and she can never reversed the effects of that aging.

For example:

Person X non oath-bound lifespan = 600 years.

Person X swears 3 oaths at age 30, when she becomes AS. During those first 30 years, she's aged 30 years out of the 600.

Person X remains oathbound for 200 years (to age 230), during which time she's aged 400 years (2X the normal rate).

Person X retires to the Kin and unswears the oaths. She now has (600-30)-400 = 170 years of life remaining, so she'll die at 400.

If that were the case, then the AS would be crazy to continue to use the oath rod. But, if the 2X aging that person X experienced while oathbound reverses affect (back to 1X) when she unswears, so that she can live out her remaining 370 years, then the AS could continue using the oath rod without undue affect on their lifespans. My guess is, that's how it actually works.