Wrong documentation for `foldMap`/`foldMap'`?

The doc comments for foldMap and foldMap' currently say that they're right-associative and left-associative, respectively. However, as I understand it, that should only apply for the default implementations (which are using foldr and foldl', respectively).

The point of foldMap/foldMap' (and Monoids in general) is that <>/mappend is associative, so it doesn't make sense to me to enforce that they need a specific associativity. Additionally, if they always had to be right-/left-associative, I don't see why they should be class methods, since I don't think there would be a better implementation than the default one.