He asks people to remember that Joe, who took over the team captaincy in the second half of the last campaign, is, despite his experience, still extremely young.
"He is such a young lad, to be 21 and already having gone to a World Cup," he says.
"People think you are fully developed but you can't possibly be at the top of your powers at that age.
"In three or four years Joe Cole is going to be even better than Joe Cole is now.
"With his character, personality, and attitude it will allow him to improve every season.
"He enhanced his reputation even more with the team captaincy and he gets on extremely well with all the players.
"Anybody who gets to know Joe Cole personally can't help to be impressed by Joe as a human being.
"When he scored the goal in the friendly game for England with the free kick and spoke on television afterwards everything he said was from the heart and you knew he meant it.
"He wasn't being false or anything other than himself; people appreciate honest people, I certainly do, and he is a very honest lad.
"He loves football and will carry on improving season in, season out.
"Joe did very well as team captain and is still learning the tactical side of the game; at 21 no one could possibly excepct him to know all the different areas about a team's tactics and what every player in every position should be doing.
"But he will learn that and only do so by concentrating on different requirements for different players through being captain.
"I feel in the six months he has had the team captaincy, and I think everyone else recognised this, it did his character good.
"Steve Lomas, though, is a vital member of the team and his experience and knowledge as club captain is very important to myself and Joe.
"I can always sit Steve down and talk things through with him like I can with Joe; we have got two very different but very good captains at the club."
Glenn has been impressed with Joe's attitude on returning to work and adds:
"Joe has come back, as always, in an extremely positive manner; he enjoys his practices every day and he works hard at the physical side of the game, the running, the agility, and the upper body strength.
"Joe Cole always comes alive when the balls are out, he enjoys playing football so much.
"I always look forward to going out to work and seeing Joe on the training ground; he normally pops his head into the staff room most mornings and asks what football work there will be - that is what he really enjoys and looks forward to."