Virtually the whole media had us despised outsiders in 69, and put in the boot big time when we won.
Clive Churchill's son wrote that his father came up with a game plan to get Beetson taken out in the Semi-Final that worked to perfection. Each Souths forward goaded him individually until he was sent off. He also admitted Nosworthy countered perfectly with his own game plan, and they didn't see it coming.
You have to remember though, Balmain needed to have the game already won for the plan to succeed.
Alan Clarkson & Col Pearce wrote in the Sun Herald that Souths needed to be careful and weren't certainties after they scraped home against a 12 man Balmain team in the Semi-Final.
Balmain was on Souths heels all season having beaten them in the first round. Tutty was sitting out the season. Norm Miller had been replaced at hooker by John Crawford, who was having trouble winning the ball and was replaced by Peter Boulton during the Final against Manly. Manly were leading that game with 90 seconds to go, Balmain were 20 yards out from the Manly line in possession when Bob Smithies at dummy half made a 35 metre pass out to George Ruebner on the wing who ran over two Manly players to score and win the Final. (Hence Ken Arthurson's sour comments in the O.P.)
Apart from defence, the 2 things I put down to the win are the brains and guile of the best half back in Sydney at the time David Bolton. Arguably part of the greatest halves combination of all time with partner Alex Murphy. They were part of the Gt. Britain team that humbled the Dragons in 1962\. Bolton then played in the 1966 Balmain team that defeated the touring Gt. Britain.
It was the Balmain forwards that made the victory possible. Gary Leo moved from 2nd row to Prop to partner Barry McTaggart, and young Joe Walsh was bought in to partner Jack Spencer in the back row.
Walsh never took a backward step. The forwards more than held their own against the giant Manly and Souths packs.