But for the shadowy former and elusive latter Thornley would probably still be playing in the FA Cup fifth round this weekend, but in the red shirt of Manchester United tomorrow rather than the blue and white stripes of Huddersfield against Derby today.
The 23-year-old was one of the brightest of Alex Ferguson's fledglings, a quick, skilful left-winger with the broad frame that, with the strongest of irony, initially suggested resistance to hurt.
He played in the 1992 and 1993 Youth Cup final teams (one win, one defeat) alongside Giggs, David Beckham, Nicky Butt, Gary Neville, Paul Scholes, Keith Gillespie and Robbie Savage and made his first team debut as an 18-year-old in 1994.
Then came a cruciate ligament injury and a spiralling and depressing descent, from the likelihood that he would be as regular as you can be in a team that has Giggs' talent to call upon to the realisation that he would have to go elsewhere to get regular football. In some it is a tale that would provoke darker feelings, but if Thornley is bitter he disguises it well.
"Of course I look back and think if only," he said with cheerful, machine- gun rapidity and in an accent revealing his Salford roots. "People said Nicky Butt and myself were at the head of the queue and Alex Ferguson told me he thought I'd make it but you can't live in the past. You have to go forward."
Thornley did that by leaving United. "I had to ask myself: `Do I want to continue playing in the reserves with a bit part in the first team or do I want to get away and play 40 or 50 games a season in front of big crowds?' It didn't even have to go to a toss of a coin. It was the more sensible option and it's proved the more fruitful."
Ferguson did not want to release his recuperating winger - he played him against Arsenal and Liverpool in last season's run-in - but a man who has let his own son, Darren, leave Old Trafford was not likely to deny a chance to others and as Thornley had been on loan to Huddersfield in 1996 it was the McAlpine Stadium he chose when Peter Jackson came knocking last summer.
"When I met the manager I could see he had blue and white blood flowing through his body," Thornley said. "He's a young guy who loves the club and his enthusiasm on the touchline is there for everyone to see. Also, it was a plus that I knew a lot of the lads. They helped me settle in.
"Huddersfield's a homely club, but you can see it's going places if we have the right playing staff and if we've got the business people in the big black chairs helping us out."
He has left United but it is unlikely to leave him. Gary Neville, who is engaged to Thornley's sister Hannah, rang him just before this interview to let him know he had been invalided out of England squad, while the Neville family and Beckham have visited the McAlpine to watch him play.
"I still see Gary a lot," he said. "I don't see Becks and Ryan as much as I used to but I keep in touch. Any of the lads I grew up with, Scholesy, Nicky Butt, I'd gladly spend the night talking away old times."
The Ryan of above is, of course, Giggs and it is one of the great paradoxes in Thornley's life that he weighed up the wealth of young central midfield talent at Old Trafford in the late Eighties and quickly switched to the flank which put him in direct competition with the most natural talent in the land.
Only Giggs' versatility allowed Thornley to play in the winning 1992 Youth Cup final team and such was the talent at Old Trafford in those days it was still at the expense of a current Welsh international. "Giggsy played up front, leaving me to my own devices on the left," Thornley said.
"I was worried I'd miss out because Ryan only played in the two legs of the final and one match in the semis, but Robbie Savage was the one who had to drop out. I felt for him, it must have been very hard. Heartbreaking."
Surely, putting friendship aside, there must have been times when he hated the sight of the young Welshman casting spells on his own left-wing territory? "Not at all," he replied with a laugh. "Better players than me are going to play second fiddle to Giggsy.
"On his day, and the prime example was the 3-2 win over Juventus last season, he's the best around. Believe it or not he'd not trained for two and half weeks before that game and he was out of this world.
"I've never got sick of him. I love him to pieces. I've known him for 11 years and he's a great lad. He's never let any of the fame go to his head. He's careful how he conducts himself off the pitch and he's a credit to Manchester United. I hope they keep him there for as long as possible because he'll win them things season after season."
The "I hate Giggsy" headlines can be safely binned then, and anyway Thornley feels more positive newsprint will come of today's tie at home to Premiership Derby County. "I've said this to everybody. I really think we've got as good a chance as we'll ever have of getting through to the quarter-finals of the FA Cup," he said.
"You couldn't get a phone call through to this place last week, the demand for tickets was so great and if we can get the stadium to the point where we are pushing 20,000 like we did for the Sunderland and Bradford games it'll be a superb atmosphere, intimidating even for a team of Derby's quality. If we can just get a lucky break..."
Thornley is owed a break of the lucky sort himself as even now he is just playing after a three-month lay-off. "I played 21 consecutive games at the start of the season and, all right, I had as couple of bad ones, but most of them I was quite healthy. I feel I'm fitter than I've ever been. I need a few games to recapture everything but I feel as good as ever I did."
For a young player who had two years of his career snatched from him, a few seasons free to put his cares and past doubts behind him is the least the deserves. Fate, you feel, owes Ben Thornley.Reuse content