The 50% 2/3 clause is a flawed improvement. At 50.00002% of turnout, there only needed to be 52,261 no votes for contract to be turned down. But if one less person voted, it would need 69,681 no votes to be turned down. Can you see how easy it is to game the vote for yes voters? If you know the vote will be close to 50%, it is better for some yes voters to not vote, as it will cause all no votes to be worth half as much.
It really needs changed. I would change it to (needs to have a lawyer overlook for correct wording):
(2) If less than half of the eligible members cast valid ballots, then a two-thirds (2/3) vote of those voting shall be required to reject such final offer and to authorize a strike. The failure of such membership to reject the final offer and to authorize a strike as herein provided shall require the Local Union Executive Board or to accept such final offer or such additional provisions as can be negotiated by it. The failure of such membership to reject or ratify the final offer shall require a second vote no sooner than 35 days from the previous vote. The second vote shall be decided by a cumulative majority of those voting. The Local Union Executive Board may opt to return to negations instead of a second vote, starting this process over.