Yes, I don't have an answer for that part and it makes sense of course, there's no reason to design an encoding that no one expects to use. On the other hand,

Yes, I don't have an answer for that part and it makes sense of course, there's no reason to design an encoding that no one expects to use. On the other hand, the above design idea (ZWJ sequences of arabic numerals with a "mode" marker) is offered free to anyone that does think they have a use for these numerals in Unicode and wants to turn it into a proper proposal.