I asked my husband about this (he was an elder for 25 years). He said if they ever come to call on us, wanting us to take the da step, he would ask them if they consider us to be members of the congregation. If they say "no", he would ask why he needs to agree to the disassociation thing. If they say "yes", he would ask why they haven't tried to encourage us. So obvious, it's funny.
Marilyn (a.k.a. Mulan)