The defending champions also won their semifinal 6-0 a fortnight ago.
"I think this title is a bit more special than last year," Tamai said.
"There was a lot more pressure on us this season to win it, and do the double, and to do it in such a convincing manner we are over the moon."
He said another big crowd turned out to support them during the final, and he thanked all the spectators for coming along to help spur them on.
"It was pretty amazing with the support. It was absolutely pumping with the music going, the barbecues going, it was a great atmosphere," he said.
"And it was great to see some of the older members and players, who used to be part of the club, come back to the club and watch. It was very humbling to play in their presence actually. It helped us play our hearts out."