Backwards Busha Battling

Sorry about the title; I just couldn't help it.

This past Shabbos (Tzav 5771) after tish, the Rebbe said that one of the ways to generate the requisite conviction and determination in order to stand up against the temptation of the yetzer hara, is to ask yourself the following: If I did such-and-such, would I be able to look at myself in the mirror afterward? In other words, imagine that you already did the aveira. How do you view yourself? By experiencing that busha (shame, embarrassment) you can guilt yourself into not actually doing it. You are fighting the battle in backwards fashion.

Rashi brings that Yosef Hatzadik was prevented from succumbing to the yetzer hara by the sight of his father's image - ראה דמות דיוקנו של אביו. The Rebbe interpreted it as saying that Yosef thought, "When I am finally reunited with my father, having done this sin, how will I be able to look at his face?" He looked ahead and imagined what it would be like to look in his father's eyes as a compromised Yosef as opposed to as Yosef Hatzadik.