[To most Jedi, any mention of the Dark Side is enough to cause alarm. Granted, said alarm was usually understated thanks to decades of emotional temperance, but it would present itself nonetheless.]

[To someone who's read deep into ancient Jedi philosophy (in both literal and metaphorical senses), however, it's a matter that brings up more intrigue than anything else, evident by the brief quizzical look that passes over Qui-Gon's face. He has his misgivings, too, after all he'd lost Xanatos to the Dark Side, but that had been its own calamity in the making. Rey's situation is different, uniquely complex, as all issues are.]

Deep connections through the Force that aren't based on Master-Padawan pairings are rare... and powerful.

[There's no doubt that both Rey and Kylo Ren embody pure strength when it comes to the Force, rivaled only by Anakin and Luke. Their potential goes well beyond simple biology like midichlorians or bloodlines. They're destined to harness and convey that strength. It makes sense, therefore, that there's some sort of bridge between the two.]

I have little personal experience in the matter, but I can say this: fixing your connection to the Force isn't a matter as simple as shutting out the other end of your bond. It's only putting off the inevitable and hurting you further in the process.