Yep, utter bollocks
If there are allergies in the family, consider a mixed-breed dog that’s been crossed with a non-shedding variety, such as the Poodle
“If there are allergies in the family, why not increase their chances of being allergic by considering a non shedding breed such as a poodle, and crossing it with something that adds the shedding breed back in..”
Genetics, mumsnet, genetics. Crossing a non shedding breed with a shedding one increases the allergenicity of the coat.
If you have a child that has allergies, just get the non shedding breed, there is no need to cross something that already is suitable to make it less so..