I’m sure, plenty of evidence backs me up.
Why is it the people with the highest vertical jumps are all very strong in regards to relative strength?
There isn’t one person with a legit 40 or more inch vertical jump who can’t full squat well over double bodyweight for reps, who has been doing weights for at least 2 years.
a nice quote from my mate JackM 
On squatting and VJ development
It’s not that huge squat equals huge vert. It’s not even that strong legs equals huge vert. If you take a group of 100 athletes and test their maximum isometric leg strength the correlation between maximum force and vertical jump isn’t all that strong. However, there is a difference between vertical jump and vertical jump IMPROVEMENTS. There’s a difference between strength and strength IMPROVEMENTS. And improving relative strength does improve vert.
To get into this a little more, unfortunate as it is, other than skill (movement efficiency), maximum strength is really the only quality that we can improve to any significant degree. It’s possible to double or triple strength levels…you can train 10 years and if you’re lucky you might increase your rate of force development, rate coding, neural processing speed etc. 5%. Truth be told you’re more likely to improve those through altering your endocrine and neurotransmitter physiology then you are training. To see the impact of those, see how many 75 year old men you can find with any quickness or speed. The main difference between 25 and 75 is the same difference between slow athletes and explosive athletes. No amount of training can turn a 75 year old into a 25 year old. Think about that.
Strength ain’t perfect but it’s really all we have to work with. It’s really more or less a shotgun approach. The muscle innervation during a jump is something like 30%. Only 30% of the fibers are firing to any significant degree. So by squatting you’re hitting 100% of the fibers to improve the force generated by those 30%. Same goes for glute ham raises, deadlifts, calf raises etc. Keep in mind no exercise is 100% specific either. I have some yet to be published research that looked at 5 different movements (jump squat, depth jump, power clean, power snatch) and the most specific movment to the VJ as far as EMG, order of recruitment etc. is actually the hang power snatch. But anyway, a better method of increasing sports specific strength IMO would be implanting FT fibers in certain muscle groups of the body. No doubt someone will eventually do that, or come close, but until then we have to work with what we have.
So it’s not pefect but it freakin works and works consistently. You can continue to increase the strenght of those 30% of available motor units and plug them into your existing movement efficiency, leverages, processing speed, neural drive, rate coding capabilities and continue getting higher and higher. Maybe if you’re lucky you can also improve those factors to some degree as well. It turns out that strength work also works well for that. Thats how PAP or the stim method works.
After thinking about that it might be clear why size in FT motor units is quite under-rated as well.
