Ever since I started with ASCS in its Directives Branch I've been interested in that question. This election it is important because lots of voters will be voting by mail for the first time, and lots of county clerks will have to compose instructions and see their voters try and sometimes fail to follow them.
Anyone remember the "butterfly ballot" in Florida in 2000? I think the answer to the question is: "sometimes". But it's often a problem to convey information from one mind to another, and often people doing something new try to figure it out themselves, only checking the manual when they screw up.