they are opened alphabetically, so we will know early on, ie Arizona is the first of the illegitimate, or skips it and goes onto the next one that is legitimate. (if he skips it, then i would assume he is using his reserve powers)
If it is opened, then the senators can object to it, and they can discuss the illegitimacy. It is not just a counting exercise, but must survive scrutiny if objected to. Thats what i also took from the above links.
