The Sharks showed they could handle the 10 interchange system with their 16-10 victory over last year's frontrunner Manly at Brookvale Oval despite being reduced to just 16 men after losing prop Ben Ross in the first six minutes.
The Sharks turned an early 6-0 deficit into a 16-6 lead before holding out a late challenge from the Sea Eagles in a gripping contest.
Cronulla coach Ricky Stuart praised the tireless effort of his forwards, Kimmorley predicting the new interchange system will help his side exploit other tiring and less mobile forward packs.
"I think the interchange rule is good. I like the fact you can't have three or four forwards coming at you for 80 minutes," Kimmorley said.
"And after 20 minutes, it showed they couldn't do it and they got a bit tired and the game opened up a little bit.
"It's good. It opens the game up a bit more at the end of both halves.
"We've got guys who can play footy. We're not just a side who do hit-ups.
"It allows you to play footy a bit rather than what we were doing last year which was four hit-ups to build pressure and you wait for the other team to make a mistake. Now you can have a bit of attacking brilliance and score some good tries."
The Sharks' narrow win was just the club's fifth in 33 visits to Brookvale and a significant boost to a side who play their first five games on the road, including a trip to Melbourne next week.
Having lost seven games by less than a converted try last season to miss the finals, Kimmorley said it was confidence-boosting to win a close contest over a side which thrived in such games last year.
"We did a lot of work in the off-season being under fatigue and doing both defence and attack and executing better when tired rather than fresh and tonight I thought we did that," said Kimmorley.
"We were under the pump by having to defend two or three sets of six but we were still good, whereas last year we might have been a bit erratic.
"They came ready to play and bashed us and got physical but we probably only had a few scoring opportunities and we were good enough to grab them.
"It showed a lot of character of the boys and we have a good camaraderie.
"Everyone said we were so unlucky last year you might be lucky this year, but you've got to make your own luck."