PHOENIXZERO
Member
It's not that adults are harder to train in the force, it's that adults fall more easy to temptation. So the key is preventing them from turning to the dark side and that's easier to instill as a child, vs an adult when you already have preconceived notions of the world and can USE the power for a specific end. Whereas the Jedi prefer to teach children a specific (I.e knowledge and defense) application of the power.
No reason an adult can't pick it up and kick ass with it- look at Luke. Two hours training and blocking blaster fire on the Falcon like he was born to. Zero telekinesis training, and he's whipping light sabers out of the snow to save himself.
Considering what Maz told Rey about the force, and Ren invading her mind and her being able to read his back... That's as much if not more "knowledge" of the Force than Luke got in A New Hope anyway. Also Anakin was using force reflexes as a pod racer before he ever met Qui Gon. Pretty par for the course for a Skywalker.
That's what I was getting at, yes. But adults being harder would have to do with, like Luke's doubts in the power of the force while training with Yoda, something a child wouldn't have, thus easier for a child but more difficult for an adult to unlearn what they've learned.