Muscle fibres are recruited maximally due to the force you apply through them, so the simple formula is:
Maximum muscle fibre recruitment = Max Hypertrophy.
What is force?.... Force is mass x acceleration
So if I want to create the greatest amount of force, my goal is to move the biggest weight ( resistance) I can, in the most explosive fashion ( acceleration) I can, so why would I ever want to not recruit as many muscle fibres as I can by lifting in any other fashion?
Slow concentrics do not equal Max force output. So why are you doing them?...Learning how to feel the muscle and gain an understanding on how it FEELS.
Muscle is a use it or lose it commodity, its taxing for your body to keep it around.
Progress your lifts, lift the concentric explosively , control the eccentric so the load is on the target muscle. Its that simple assuming technique is on point.
I could create some kind of gimmick, tell you random words that mean nothing and try to sell it to you. Most people would lap it up because they want the secret. "Tell me the secret to getting big" The secret is squat 6 plates, pull 7 plates , press 5 plates. Why do people not want to hear this - because it's really really hard. It's mentally challenging knowing " OK is Monday... I have to squat 6 plates AGAIN today, but it's easy to just pump stuff up and trick yourself that some kind of deep burn is going to do much of anything.
People will challenge this all day. This is my opinion, this is what i've found works with the vast majority of clients who want to build muscle...Yes, there are certainly other methods and im learning all the time which is why I love this game.
Remember... stop and think. Dont get lured into marketing mumbo jumbo.
Keep it simple :)