From Abraham Lincoln in 1842, speaking about his preferred approach:
It is an old and a true maxim, that a "drop of honey catches more flies than a gallon of gall." So with men. If you would win a man to your cause, first convince him that you are his sincere friend. Therein is a drop of honey that catches his heart, which, say what he will, is the great highroad to his reason, and which, when once gained, you will find but little trouble in convincing his judgment of the justice of your cause, if indeed that cause really be a just one. On the contrary, assume to dictate to his judgment, or to command his action, or to mark him as one to be shunned and despised, and he will retreat within himself, close all the avenues to his head and his heart; and though your cause be naked truth itself, transformed to the heaviest lance, harder than steel, and sharper than steel can be made, and though you throw it with more than Herculean force and precision, you shall be no more be able to pierce him, than to penetrate the hard shell of a tortoise with a rye straw.
> A common expression would have us believe that ‘you can catch more flies with honey than with vinegar’. But this is not true in the case of the fruit fly Drosophila melanogaster (xkcd, 2007).
I don't think that applies here since the poster didn't disagree with the excerpt, they only pointed to a correction -- the fact that an aspect of conventional wisdom had been rendered untrue via research.
It is an old and a true maxim, that a "drop of honey catches more flies than a gallon of gall." So with men. If you would win a man to your cause, first convince him that you are his sincere friend. Therein is a drop of honey that catches his heart, which, say what he will, is the great highroad to his reason, and which, when once gained, you will find but little trouble in convincing his judgment of the justice of your cause, if indeed that cause really be a just one. On the contrary, assume to dictate to his judgment, or to command his action, or to mark him as one to be shunned and despised, and he will retreat within himself, close all the avenues to his head and his heart; and though your cause be naked truth itself, transformed to the heaviest lance, harder than steel, and sharper than steel can be made, and though you throw it with more than Herculean force and precision, you shall be no more be able to pierce him, than to penetrate the hard shell of a tortoise with a rye straw.
http://www.abrahamlincolnonline.org/lincoln/speeches/tempera...