The Blues keeper has kept two successive league clean sheets.
And this follows interim chief Benitez ordering the European champions to defend as a team - with even the flair players in midfield told to dig in.
Cech, who will make his 400th club appearance at Everton on Sunday, said: "We look better organised.
"That is the difference. We were conceding so many goals. We were very open and suddenly we are defending as a team much better.
"I think that is the key because we were not defending well as a team.
"We were conceding too many goals and now suddenly we are back to our ways where we are difficult to score against and that is a big help.
"And, of course, we have the quality players who can score goals. Against Aston Villa we scored eight goals but against Norwich one was enough, which is good.
"You need the whole team to defend. We have really attack-minded players and sometimes we were not making the right choices in terms of defensive transition.
"I think what has improved is that we are pressing the ball much better, so it gives us the time to re-organise and I think this is the most significant change.
"Benitez came to us with slightly different ideas of what we were doing on the pitch and so far it has been working. So hopefully it will continue this way.
"We beat Norwich 1-0 and it shows we were resilient and well organised. And as well, we were patient enough to score one goal and control the game until the end. This is a very good sign.
"It is never easy when you win 8-0 and suddenly everybody thinks, 'Ah, easy, another game'."