Regarding speed work, Louie does advocate fast, overspeed eccentrics. However, you have to consider that he and all the other lifters are watching each other like hawks, making sure positioning and form are maintained 100%. I have found that too much focus on speed in the eccentric can cause a lifter to get loose on the way down, which throws everything off on the concentric, so for a lifter trying conjugate training (specifically, dynamic effort method) for the first time, I would recommend putting an emphasis on controlling the weight and building tension on the eccentric, and focusing on speed and explosiveness on the concentric only. As you develop more understanding and skill, you will find yourself able to move quicker on the eccentric while maintaining tightness and form.
As for bands/chains/weight releasers/ etc… I would recommend to just start with fairly light bands, maybe only 10-15% tension (as opposed to the 20-25% generally recommended) until you feel you really understand their function. Then start, one at a time, experimenting with different things.
One of the main functions of bands that I feel gets overlooked a lot is that they allow you to push with 100% force into submaximal weight without your form going to shit. Consider this… if you squat an empty barbell as fast and hard as possible, it will jump up off your back. If you squat a broomstick with bands attached to it, so that the band tension at the top is the same as the weight of an empty barbell, it won’t jump off your back. Normally, if you’re squatting <70% you have to throttle back how much force you put into the bar each rep, because otherwise it will move to fast and bounce around. So basically, you teach yourself to not put 100% force into the bar, which is a terrible thing to practice for powerlifting. With bands, you can still put 100% force into the bar even at submax loads, so you reinforce the habits you want to carry over to the platform.