The Carlton coach, an outspoken critic of the cap proposal after pioneering rapid rotations at Collingwood, met with the AFL's Laws of the Game Committee on Wednesday afternoon.
After the meeting, Malthouse said he was pleased to have been invited to address the committee, adding that he was convinced it was "seriously looking at every avenue to make the game better".
However, he said he had only found out through the media that there would definitely be an interchange cap, after AFL chief Andrew Demetriou revealed on Melbourne radio on Tuesday morning that the AFL Commission had already decided to introduce the rule in 2014.
"I might be a bit slow in listening to the Australian news, but what (Demetriou) didn’t say was the number," he said.
"I would have been horrified had he said 'that's the number,' because we don’t know the number …
"I suppose in many respects I'm not surprised that there's going to be a cap, but I guess coming out like that was a bit surprising."
Malthouse said every club would have an optimum rotation number in mind, but would not disclose his own preferred figure.
"If you took that over 18 clubs and knocked off the bottom one and the top one … then you’re going to get somewhere near the number that most of the clubs think is the right number," he said.
"I hope it is seriously looked at (and) that it is very, very generous."
Malthouse said 80 rotations, even in reduced-time matches in the NAB Cup, was "already far too few".
"I cannot play some players in this NAB Cup series because they can’t fit in to the rotation thing and it will put them at risk (so) we don’t play them," he said.
"We're already being denied seeing some of our better players who are coming off injuries playing in this NAB Cup series. We don’t want to see that expand into the main season."
Malthouse said any conclusion on the eventual number needed to be backed by considered research, and repeated his longstanding view that all evidence he has gathered through sports scientists suggested that the increase in rotations from the mid-2000s had contributed to a decrease in fatigue-based injuries.
Of his public debate with former Richmond teammate and Laws of the Game Committee member Kevin Bartlett, Malthouse said: "Old Tigers have a difference of opinion, but that's fine."
However, he said he was disappointed by Bartlett's suggestion that coaches are too blinded by self-interest to consider what was best for the game.
"I take exception to that call, and I'm sure every coach does," he said.
"We definitely want to win, but we have an underlying passion for seeing Australian Rules football be the greatest game it is."
He also cited examples of coaches making suggestions at coaches' conferences that went against their own club's interests.
"I still recall (then Port Adelaide coach) Mark Williams, who had a very strong assault side on the ball and on the man and one (player) was Byron Pickett, who was a wonderful exponent of the shirtfront," he said.
"But Mark was the one who volunteered … that this may be bad for the game. He was virtually nailing the coffin of that player at the detriment of his football club (but) for the betterment of the game.
"We spoke 20 years ago about ruckmen doing their knees. How can we do something to protect them? Some (teams) had strong rucks, some didn’t have strong rucks. Again, it was for the betterment of the game."
