In the first example generated by Get-Help Add-Member -Full, the text reads:Adds a new member even the object has a custom member with the same name. It should readAdds a new member even if the object has a custom member with the same name. There is a missing 'if' between the words "...member even" and 'the object has...'This is true of both the downloaded and online help text.
Where do you see this documentation issue.