Australia ran out 32-15 winners in Dublin on Saturday, leaving the likes of Brian O'Driscoll and Jonny Sexton also licking their wounds.
And although O'Connell was celebrating Down Under this summer he admits there is still plenty to focus his mind when it comes to his country.
"Joe talks about the inches in rugby matches, and I think Australia won a lot of them," O'Connell told the Irish Times.
"They got a few scrum turnovers, and a few at the breakdown too.
"You could see how high their emotion was in comparison to ours when we got our turnovers, and that was disappointing from our point of view.
"I suppose for a few of us we've a little bit to learn under Joe, there's a lot of technical stuff we need to get right.
"But you can't lose track of that intensity and that aggression that's required at Test rugby as well.
"A lot of the stuff is quickly rectifiable, defending mauls close to your line, you just can't concede tries there, and that's a really disappointing aspect for us.
"The two tries they scored in the first half, they went width to width and it was disappointing how tight we got there.
"It was something we discussed in the week that we needed to hold width if we were going to take line speed. So I think some things are easily rectifiable."