If a parent has a low self esteem their child is also likely to have low self esteem.

Yes... and studies show that this is largely due to genetic similarity, much less so to parenting style.

Being secure in herself increase the chance that she will do the right things at the right time signal her self confidence to the child.

Which still means that it boils down to what the mother does.

The thing is, no one can see what you "are" except by what you do. Your argument seems to be "doing things for the right reason will lead to doing the actual right thing, instead of implementing some standard recommendation of what the right thing is". Granted. But the thing that matters is still the doing, not the being. "Being" is relevant only to the extent that it makes you do.

Oh, and as for this:

There a drastic difference between a child observing: "Mommy hugs me because she read in a book that good mothers hug their children and she wants to prove to herself that she's a good mother and Mommy hugs me because she loves me".

There's a third possibility: "Mommy doesn't hug me, but I know she loves me anyway". Sometimes that's worse than either of the other two.