Two things: That first statement isn't canonically true (as far as I know), so I'd say you need some more circumstancial evidence to back up that claim. I don't disagree, but just saying.
Also, Ganondorf is a master of dark magic. Does that make him a "dark" type? I would do it if I were at a computer, but I suggest looking at a clairifcation of the typing system on Bulbapedia to see if that makes sense (calling Gdorf a Dark type).
You bring up a good point there. I hadn't considered Ganondorf might actually be considered Dark-type. Interesting.
Anyway, telekinesis/psychokinesis, are described in this manner:
the purported ability to move or deform inanimate objects, as metal spoons, through mental processes.
All right, so we know that Ness, Mewtwo and Lucas can all bend inanimate objects at the very least. What else we got in the ol' dictionary grab bag?
alteration of the state of an object by mental influence alone, without any physical intervention
Interesting. So, someone with telekinesis can technically alter the state of an object simply by thinking? The brain is a fragile thing, you know. Let's dive back into the bag:
An uncontrolled, maniacal outburst, resulting from defective inhibition
Whoa. Now we're getting into some dark stuff. Still, those three definitions tell us what we need to know. Ness, Lucas and Mewtwo can all:
1. Move and deform inanimate objects.
2. Alter the state of an object simply through thought.
3. Release psychokinetic energy in uncontrolled outbursts.
Number three, especially, describes PK Rockin'/Love perfectly. It probably also describes the attack Psychic, as well.
Now, let's give you and Ravio the benefit of the doubt. Let's say that Mewtwo, Ness and Lucas don't have the cognitive prowess to target someone's brain and, instead, rely on crushing or concussive force alone through telekinetic/psychokinetic power. How much force is required to crush the Human skull?
"a force of 73 Newtons is enough to cause a simple fracture, this
force is the equivalent of walking into something solid. An
unrestrained adult fall from standing has been shown to produce a
minimal force of 873 N which is more than enough to produce a skull
fracture."
Interesting. It only takes 73 Newtons to cause a skull fracture, and the minimal force of an unrestrained adult fall from STANDING produces more than ten times the required Newtons to create a skull fracture. To put that into words that are easier to understand, 873 Newtons = 196.2504 lbs of force required to fracture the Human skull. Naturally, there's a lot of variables that decide how much energy and pressure it requires to crush a Human skull, but if only about 200 lbs. of force is required to produce a skull fracture, that's not much more we need to crack a skull, let alone squish it completely. What can create about 200 lbs. of force that we know of in the real world? What about boxers?
- An oft-cited 1985 study of Frank Bruno, who'd go on to be WBC heavyweight champ, showed he could punch with a force of 920 pounds in the lab. Researchers extrapolated that to a real-life blow of 1,420 pounds, enough to accelerate his opponent’s head at a rate of 53 g — that is, 53 times the force of gravity.
Holy crap, the guy punched with a force of 920 pounds?! That's almost five times what's required to fracture the Human skull! Considering how many Pokemon there are that punch fast and hit hard, especially Fighting-types (for example, Machamp purportedly punches 1,000 times in two seconds; Hitmonchan punches at the same speed of a bullet train (310 MPH)), is it really that much of a stretch that Mewtwo, Ness and Lucas can, if not brain-puree someone psychokinetically, crush their skulls like we crush bugs? Of course, we don't really have any evidence of what kind of psychokinetic force that they can create, but if someone falling, unrestrained, from a stand can fracture their skull; if a normal Human boxer can hit someone hard enough to cause bone fractures and concussions (and sometimes, in the right circumstances, even death); I think we can give Mewtwo, Ness and Lucas the benefit of the doubt here.
Similarly, if they're creating enough force telekinetically to crush the skull - which is a surprisingly resilient fusion of bones - they can certainly focus enough telekinetic energy to break bone, at the very least, and last I checked, people need those to function properly.
tl;dr: Mewtwo, Ness and Lucas, even if they can't brain-puree someone, can likely hit them in the head or apply pressure hard enough with telekinetic force to crush their opponent's skulls.
It doesn't say "The target's brain". It doesn't say "Is torn to shreds with mental power". It says "hit with a strong force." Punching someone is hitting them with a strong force.
All those Pokedex entries say is that it's pretty dang strong. Not "strong enough to instantly destroy the living definition of power who is CANONICALLY INVINCIBLE TO EVERYTHING BUT THE MASTER SWORD/LIGHT ARROWS." Not "The most powerful thing ever automatically who overrides any super murder abilities anyone else has." No. It implies Mewtwo is pretty tough. That's it.
In order to generate a Psychic attack, it still has to utilize telekinesis, which it DOES say. The question is whether or not Ganondorf can have his skull crushed. If he can be stabbed, I think it's fair to assume he can. See above.
At least we can agree that Mewtwo's pretty tough, but I'm willing to concede that it's possible Ganondorf might be sitting at the #1 spot even with all that argument, though.