While his sides are often praised for style, artistic merit and attacking verve, he believes that clean sheets secure the perfect ten.
"Clean sheets are important to us if we're going to do anything," said Glenn. "I said to the players in pre-season, I got them all together and explained that, strangely enough, people will think we're going to play passing football and we're going to do this and that.
"But it's how well we defend as a team, a team, that will determine how well we're going to do this year. I knew the players I was bringing in, I knew the system we were going to play would benefit them and we would score goals and play good football. Because they are intelligent players."
It was due to this fact that Glenn was an agitated touchline observer during the closing stages of Sunday's FA Cup win over Tranmere - even though we were 3-0 up at the time.
"It's all about how we defend and I was very annoyed at the end because they had chances that really shouldn't have been there.
"Until we learn that lesson we're perhaps not going to achieve what we can achieve."
On the subject of defending, Anthony Gardner and Goran Bunjevcevic return to action for the reserves at Coventry tonight, both hoping to put themselves in the frame for Cardiff on Sunday.
"Ben Thatcher picked up a bit of a whack, which he always does! He's a bit bruised, but that shoudn't take more than a couple of days to settle. We've not picked any more up ahead of the weekend so I've got a nice headache in terms of selection.
"Anthony is somebody who is chasing it. He's out there and we're giving him physical sessions. He'll play in the reserve game on Wednesday and this one has gone against us a bit. He's fit and his knee feels okay, but he needs a game under his belt."
Glenn Hoddle says that efficient defending as a team is the key to marking this down as a season of achievement.