The Swans were right in the contest during the final quarters of both games, but the Hawks and Magpies each proved more composed at crucial times to eventually take the four points.
"Individually, guys are having a go and they’re working really hard, but our ability to play as a team is certainly not as good as what it could be,” Roos said on Monday.
"I definitely think our ability to make decisions under pressure is certainly not as good and again, that comes back to having a different team to '05 and '06 and '07.
“That’s going to come; it’s going to come when guys get used to playing with each other.”
Forward Michael O’Loughlin is one of several Swans failing to match their past output, kicking just three goals in his past five games.
Roos said the veteran’s form slump could be attributed, in part, to the number of new players in the side.
“Mick’s really struggling at the moment, and I think part of it is just Micky getting used to Nick Smith and Kristin Thornton and Ed Barlow, guys like that, coming through the midfield,” Roos said.
“[But] our forward entries on the weekend were terrible. In the first quarter, I think we had seven unpressured forward entries that just resulted in Collingwood getting the ball.
“That’s the synergy between our midfield, defenders and our forward line just not what it should be at the moment. We’re winning the ball, but we’re not getting anywhere near enough value out of that.”
Despite his team’s poor decision-making against Collingwood, Roos said he was pleased that the Swans’ tactical tinkering appeared to pay off.
The home side racked up 84 more possessions than the Magpies at ANZ Stadium with an almost-equal split between kicks (217) and handballs (201).
In contrast, Collingwood had almost two kicks for every handball (225 to 109).
While he emphasised that tactics were no substitute for effort, Roos said the Swans would again look to adjust their style against the Crows.
“They play a full-on zone; they’ve really followed the Hawthorn model. It is a little bit different, tactically, to Collingwood," Roos said of Adelaide.
“Certainly we haven’t had much success against them either, so we’ll need to look at playing a lot better against them as well.”