The Club's articles (filed upon formation with the earliest version of the Constitution) provided for an odd number of BoD members and therefore no facility for any member to have a casting vote in the case of a tie. I can't recall any occasion where, as a result of someone abstaining for example, that has ever been a problem).
Having an even number of BoD members will likely cause that to occur frequently though.
Given that Brenda's stipulation was for these two extra positions to be elected in alternate years, there would be a year at least with an even number of members. It's even possible there might only be one single nomination between both positions.

Therefore, after consultation between Brenda and legal counsel it was decided these positions should be non-voting.
Once both positions are filled then the subject of voting rights for the 2 at large members can be revisited.