The boss reasons that the earlier games were beneficial mostly for fitness reasons and the blooding of promising youngsters to give them a taste of first team action.
The 4-0 win over Crystal Palace was where he started working on the shape of the side and tactics and it was cranked up for the trip to Feyenoord.
"We started that on Sunday," said Glenn. "The other games were a progression, a mixture of looking at some youngsters and having plenty of matches to get fit.
"We started probably switching in and working on a few set plays, shape and tactics at Crystal Palace and I think we saw the difference in that performance straight away.
"Against Feyenoord we did it and at Watford we tried to do it with a less experienced side.
"It's already begun and it will be no different now with Celtic and Lazio because we are looking at Everton in the first game.
"You never 100 per cent get it right because you don't know who you are going to lose between now and the end of the season anyway - or who might just return in time. But the majority, 80 per cent, of the work is going to be put in."
Glenn is content with the progress made during the pre-season campaign and points out that Spurs finished the stronger in Rotterdam on Sunday.
"The boys look fit, on Sunday they looked fit even at the end. It was a big pitch, a hard game and they had plenty of running - we looked like the team that was going to get the winner at the end.
"That's a good sign in pre-season. Results don't really mean that much, you've got to get off to a flyer in the Premiership, that is the major concern and objective.
"I'm relatively pleased. I could have done without the injuries though. It's out of our hands to a certain degree, but we'll battle on."
Glenn says that tactics and team shape is coming more into play as pre-season enters the business end with the visit of Celtic and Lazio.