Bozo:
They only played 22 rounds back then, so the GF replay was the 28th premiership/finals game they played in, in 1978. Last Friday night's game was the 2012 team's 27th.
They didn't train every day for 10-11 months or so leading up to it. They used to start as late as Jan/Feb in those days.
They didn't have midweek interstate games played at the intensity of today's games.
They did not have a first year coach guiding the team's fortunes. They had one who had guided them to a title two seasons earlier.
There was no salary cap so theoretically they could buy 13 international standard players, if they wanted to, to fill their 13 allowable 'import' positions under the rules in place.
There were only 12 clubs involved, so theoretically you had a better chance of winning anyway, provided you had a high quality roster. Which Manly did.
They weren't the defending premiers and all that goes with it. St George missed the finals that year.