Vince taught that “bent-over squats” for most are not a true quad developer. He found that students would cheat and leverage themselves in the movement to produce a great butt, hip, and stomach expander.
However, Vince did acknowledge that in a few cases involving what he called “genetic superiors,” bent-over squats could be used. These individuals would have very small hips and short femurs that allowed them to squat in a fashion that allowed for quad development without overemphasizing the glutes.
Vince used Sergio Oliva as a good example of one who could get away with bent-over squats, but he felt most were not built to perform squats as a true quad developer.
Remember, when you widen your hips, you immediately give the appearance of narrower shoulders. A better quad developer would be exercises like hack or sissy squats.