At £3.25million for a current England international, the signing of David from Aston Villa last summer raised more than a few eyebrows.
And, even a year on when transfer fees have, for the most part, readjusted, it still looks like excellent business.
"I have got to say the transfer fees have dropped off the side of the earth - they have plummeted," says Glenn, "but last year they were still very high - and when you think what we paid for him, we feel we got him for a fantastic price and genuine value for money.
"I think he proved that when he came back into the side in December with some of his performances."
Now Glenn is looking for David to inspire the Hammers to a first win of the season, while the player himself looks for his first clean sheet of the campaign.
"We have got to start winning matches and hopefully that will happen tomorrow," says Glenn.
"Us and Southampton are the two teams that haven't won this season, and the whole club is desperate for that win to get our season going."
As for the club versus country debate that is currently popular, Glenn, who of course knows the situation from both sides of the fence having worked with England, says: "You have to consider everyone's point of view - the England manager, the club managers, the players, and of course the supporters.
"There is no doubt that if you make more than two or three substitutions it has got to disrupt the rhythm and the team play.
"From my memory, whenever there were lots of substitutions in the second half it was never as good as the first, which means it is less of a spectacle for the supporters.
"But you ask that player who gets on for the last 15 minutes to win his first cap, and who might not play again, what he thinks of these friendlies.
"I think you could make a good case for when there is a free weekend, or a midweek slot, for a friendly international that you should instead get the players together and have as many practice matches as you want.
"I am pleased to say that when Sven had an opportunity to play a friendly a few weeks ago he chose not to, but West Ham would never stand in the way of our players who are selected, because it is a massive honour both for them and for the club.
"We were delighted that Saturday's friendly against Portugal ended with three West Ham players on the pitch."