He admits the impressive Barclays Premier League debut of 18-year-old George Thorne in the Baggies' dramatic, final-day 3-3 draw at Newcastle has got the Academy ranks buzzing.
"Since the new head coach came in it has been a really positive time for the Academy," Harrison told the WBA website.
"In the last six weeks of the season those two were named in the 19/20-man squad for every game.
"That culminated in George making his Premier League debut at Newcastle. Roy has been fantastic in including a number of boys in training, some for a day or two, some for a week, etc.
"Certainly, he has had a good look at the players - and that's all we can ask for really.
"I have found the last two to three months a very positive period. Even on the days when the first-team players have just been doing a cool-down the head coach has gone out and worked with the young professionals.
"None of the young professionals could say they haven't had the chance to impress the head coach. In previous regimes they have always had a little bit of a sniff.
"But in the last three months we've never had it so good in that respect."