The new mum has slammed the dancing show claiming they instructed the presenter on what to say, instead of allowing him to come up with his own humorous remarks.
"Bruce is best when he's not scripted," she insisted. "His wife invited me to his stand up once he had left the show and he was incredible.
"Two hours, one man show – he was outstanding and you never got to see that on Strictly because he was scripted. That was a mistake."
Kristina, 39, added that bosses should never have given Sir Bruce a script, telling The Sun: "He is the best when he's telling jokes without being told what to say."
Kristina said that Bruce was better when he isn't scripted
Sir Bruce Forsyth in pictures
Mon, February 22, 2016
We take a look back at Sir Bruce Forsyth's glittering 75-year showbiz career…
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Bruce Forsyth in pictures
Ben agreed that Sir Bruce was an entertainer who didn't need a script
Bruce is best when he's not scripted
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And, her partner Ben Cohen agrees, commenting: "Bruce is an entertainer. Not just vocally but physically with his dancing as well – he knew the show inside out."
Sir Bruce left Strictly Come Dancing three years ago as his health began to deteriorate but he has made an appearance on the Christmas specials.
Last November, his wife Wilnelia opened up their difficult year as the veteran presenter continued his lengthy recovery following two life-threatening aneurysms.
The 59-year-old said that his health was still up-and-down as she admitted they "sometimes cry".
Sir Bruce left Strictly three years ago as his health began to deteriorate
Wilnelia said that some days are better than others for Sir Bruce
She told YOU magazine: "The operation took his energy because of his age, there's no question about it. Some days are better than others. On the not-so-good days, he tries to rest."
Wilnelia went on to reveal that she tries not think about what may happen if his condition worsens.
She confessed: "I hope I'll be prepared somehow, but it doesn't feel real. He's the man I fell in love with because his brain is there."
Express.co.uk has contacted a representative for the BBC for comment.