Disclaimer: everyone's experiences vary, mainly because roosters are individuals.

What I stated above may not hold true in some cases.
However, after fighting aggression with aggression, I've learned a thing or two. Every cockerel who dared challenge me progressively became an unmanageable monster who flogged anything living, breathing. Though it's entirely possible this was in their genetic makeup, I find it too uncanny to be coincidence. 35+ roosters, all meaner than snakes? It's far more likely my technique failed miserably.
Last group of 14 cockerels was handled differently. Two decided it would be a bright idea to wing dance/flare hackles/bite my toes. Instead of giving them the gratification of reacting in desired fashion (thus fueling the fire), I either ignored, or scooped said boy up for kisses. Surprisingly, they gave up, and are now two of the very best roos imaginable. Coincidence? Maybe. But after the volume in which we flew through roosters without a gentleman in the bunch, I'm inclined to think otherwise. Just keep in mind, my way doesn't always work.....no method has a 100% success rate.
Best wishes for successful correction, however you may choose to go about it!
~Alex