I disagree with some of the above.
"Muscle confusion" is just plain silly. By all means certain muscle groups require various movements/angles. No confusion necessary.
The way to grow is simple. Lift something heavier than you did the day before with enough volume to trigger a growth response AND eat enough food that you have the raw materials to grow.
Yes, that means you can essentially do the same workout over and over for YEARS and make great progress. The "change" that happens is over time, you are lifting more and more weight thereby changing the stimulus. Personally I ran the same program for over 3 years and had what many would consider fantastic results. (dont forget the key part about eating for your goals as well).
Drop sets are fatigue based training. For your average weight lifter, 90% of the muscle growth you will achieve in building size is myofibril (new cells). 10%+/- is sarcoplasmic (extra fluid / nutrient uptake). Fatigue training is the sprinkles on the top of a sundae. NOT the icecream. The only people that actually get truly big off that type of training have to rely HEAVILY on drugs to achieve it. Those are huge guys you see who are 'weak'. (so yes, you can get big doing lots of fatigue training). You will also lose it VERY fast as soon as you stop the drugs or training. Contrast that with adaptations due to lifting actually heavy weight (compared to weight that just feels heavy because you dont rest) your muscular growth will be more permanent and less dependent upon outside compounds to maintain. That said, push far enough past natural limits and no type of training will allow a guy to hold on to ungodly amounts of muscle built either way. But the "strong" big guys hold their physiques much better than the big like a balloon guys.
Negatives:. GREAT with caution. It is the eccentric motion that does the most muscular damage. Therefore, if you are going to use them, use them sparingly. Like maybe your last set only and only one exercise. If you need negatives, you are not trying hard enough lifting in your normal sets. In the 9 years I have been back in the gym (and going on 20 years of training), I can count the very few times I have done negative work. (most was when I was young and stupid and thought killing yourself in the gym was the way to grow).
Last point, is there is a lot of study that shows RPE (Rate of perceived exertion) is often INVERSELY proportional to actual muscle stimulation and signaling required to grow muscle. Meaning, the harder you think you are working, the crappier your workout just might be. A great example was I was running 5/3/1 and did not ever feel like I was even training hard or getting any kind of 'pump'. I continued with the progression as dictated as I know there are many who came before me who paved the pathway and I would follow. At about the 9th week, I totally hit the wall and found myself so run down I had to deload. (all this from workouts I never felt were doing anything for me). Over that short period, ALL my major lifts went up (which for a guy who has been training as long as I had at the time is a feat in and of itself). So dont be 'that guy' who is screaming in the corner, running down the dumbbell rack until he gets to the 5 lbs and cant move his arms. Unless you just love that, you are probably doing more harm than good. And again, unless you are taking very large doses of anabolics, no one can adequately recover from that method of training constantly.
My statement is this..... IF there is progress to be made, the "best" (meaning fastest and most efficient) is by using a pre-formatted periodized plan AND eating a calculated surplus. (add in anabolics and you have a the most ideal situation you could hope for). The worse your training is, the more you will rely on anabolics to progress....and the less likly you will be to hang on to your gains when you stop taking said substances. Once you get to the point where progress has all but stopped.....it really does not matter what you do. It takes very little to maintain. When I am asked, I tell people all the time NOT to do what I do. It is a total waste of time. IF I had progress that I could be making, I would be training a whole lot differently.
I told this to a guy who asked when I was doing shrugs and my back/traps are pretty strong visually on me. He asked about getting his traps big and I told him DONT shurg. This is a waste of time. DEADLIFT. I shared that up until 2 years ago, I never did a shrug. I would however do quite a bit of deadlifting and heavy standing OHP (both great trap builders).
Just my ramble.....