"I thought 'Oh my God, what have I stepped into here?' But that is just his passion and he shows it.
"He can also be really calm and sensitive, he works on both levels and that is why he is a good coach.
"But if he thinks someone is not trying or working or isn't bothered, that will really ignite his fiery temper."
UK Athletics chairman Ed Warner echoed Sotherton's sentiments, saying: "It is very easy to make a caricature of Charles, but Kelly has it absolutely right when she compares him to Jose Mourinho.
"He's not only got the strong personality and the ability to cut through the nonsense and tell it like it is, but he's got a great understanding of his sport and phenomenal technical ability.
"If you speak to the athletes there is a high degree of respect there, but there isn't fear and I think that is a key dividing line.
"It's easy to come across as a hard taskmaster but if you have no substance underneath and an understanding of what is required and the nuances of athletics you would be built on sand and he is built on strong foundations."
GB'S RECORD EUROS MEDAL HAUL
GOLD (6): Mo Farah (10,000m & 5,000m), Phillips Idowu (triple jump), Andy Turner (110m hurdles), Dai Greene (400m hurdles), Jess Ennis (heptathlon)
SILVER (7): Chris Thompson (10,000m), Mark Lewis-Francis (100m), Christian Malcolm (200m), Michael Bingham (400m), Michael Rimmer (800m), Rhys Williams (400m hurdles), Men's 4x400m relay
Since becoming UK Athletics head coach in September 2008, Van Commenee has seen the GB team achieve their best medal haul (six) since 1999 at the biennial World Championships and now a best-ever 19 at the European Championships, beating the 18 from Split in 1990.
"He would probably say it doesn't owe too much to his influence," Sotherton told Gabby Logan's BBC 5 live programme.
"But when he was my coach he made my feel everything was on the line, that you have to live and breathe athletics and be in these specialist places. I think he has made everyone feel that way.
"I think what [performance director] Dave Brailsford did for British cycling is what Charles is doing for athletics - it is like that. He is trying to pool resources into two places so everyone has access to the same medical and training facilities.
"With all the injured athletes at the moment [Sotherton, along with the likes of Christine Ohuruogu (400m) Greg Rutherford (long jump), Goldie Sayers (javelin) and Jo Pavey (10,000m) missed out on Barcelona] I think we left eight medals back home.
"But we still produced the best-ever performance at a Euros and I think that is testament to how UK Athletics is putting together a good system."
Pavey, who would have competed in Barcelona but for a toe injury, has returned to the sport this year after taking a year out to have a baby.
She attended the team's holding camp in Portugal before the championships and believes the team spirit and professionalism has markedly improved under Van Commenee.
The 36-year-old also believes the Dutchman's "hands-on" approach is paying dividends.
Van Commenee encouraged by GB progress
"He is really fair," she explained. "He does things one-to-one, sits down with individual athletes and asks you questions and makes you justify your decisions and why you are doing certain things.
"I think that is really good for all of us. He makes us get the best out of ourselves by asking what we can do even better. It is definitely a hands-on approach and brilliant for the team.
"They have done us proud in Barcelona and going towards the Olympics it makes people interested in the sport of athletics and gives the public people to cheer for."
But Sotherton backed that stance, insisting her former coach was right to criticise those who had under-performed.
"You have to be angry," she added. "They invest time and money in relays. They practice all-year round, not just two weeks before a major championships.
"I think the women's team were a shambles - they could have done so much better. In their interviews afterwards, no-one took responsibility for their poor performance, whereas at least Mark Lewis-Francis took responsibility and said he and Marlon Devonish messed up.
"When they do badly, they should get an ear-bashing."
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