Malthouse told AFL.com.au he wouldn't know how ingrained his players' grasp of the game plan was until they had to execute it under the pressure of a home and away game.
"The test is all about pressure and we know that the AFL (premiership) season compared to the NAB Cup season is more acute," Malthouse said.
"It's the old thing about the NAB Cup, you get beaten and you go, 'Well, we'll work on the process.'
"In the [home and away season], if you get beaten it's one less game you've got … to win enough games to make the eight.
"Everything is far more desperate. When the game's in the balance, can you do it?
"I don't know how long that's going to take."
After his team's 40-point loss to the Brisbane Lions in last Friday night's NAB Cup Grand Final, Malthouse said the Blues might need two or three months to iron out shortcomings the Lions exposed in their stoppage play, crumbing and run.
But Malthouse told AFL.com.au he was still hopeful the Blues could execute their game plan effectively from round one, saying the their ability to play with intensity in the NAB Cup had been affected by the cap of 80 interchange rotations.
"The effect of 80 (rotations) I thought was quite compounding for us," Malthouse said.
"We ran the same amount of kilometres (as a usual game) but we didn't have the same intensity.
"Do I draw that to the 80 or not? I'm not sure."
Malthouse said his players had embraced his different game-plan from the moment he took over as coach from Brett Ratten late last year.
Asked whether it was possible for the Blues to adapt to those game style changes quickly enough to contend for this year's flag, Malthouse refused to put any limits on his team.
"We've got a side that is very willing and they're looking to get everything right, so I don't think there's any restrictions necessarily on people to say how long it takes," he said.
"I mean, how long is a piece of string?
"There's no [rule] that says that this takes this long and therefore you're out of calculations."
Nick Bowen is a reporter with AFL.com.au. Follow him on Twitter: @AFL_Nick
