Okay, I’ve got some more details.
Short version - it’s DieBold’s fault!
Okay, not really, but a computer glitch.
It wasn’t a secret ballot, because the Synod is a deliberative body. Votes are recorded, just like in Parliament or Congress.
They were using some fancy computer voting system. Each delegate went to one of the machines, logged in and voted. The computer had been pre-programmed with all the delegate’s names and which of the three orders they each belonged to, so the votes would automatically be tabulated by name and order.
After the vote was announced to be one vote short, supporters of the motion asked for a print-out of all the votes.
They reviewed the tabulations and discovered that one delegate, a priest, had been improperly registered as laity.
He had voted in favour of the measure, but his vote had been listed as cast by a lay delegate.
Once the error was discovered, they corrected his registration and his vote was transferred from the laity tally to the clergy tally. Even with the vote taken out of the laity tally, there were still enough votes to meet the two-thirds requirement for the laity.
Adding his vote to the clergy tally, however, pushed it over two-thirds, and the Primate declared the motion carried.
And the ultimate irony is that the delegate who had been improperly registered was the General Secretary, who had overall responsibility for the smooth running of General Synod! Oops.
He publicly apologised to the General Synod for the monumental balls-up.
(Okay, he may not have used that particular phrase, but that was the gist of it. )
So, motion passed, but because it amends doctrine, it has to be approved a second time by the next General Synod, three years from now, by the same triple super-majorities.