I see such a method as cutting creativity because you're automatically limiting the story you want to tell in ONE chapter to 1-2k words, which isn't to say it can't be done, but it just feels like a destructive limitation. I write until the story of the chapter is complete- Like if you were watching an episode of your favorite show. Would you want it to randomly end smack dab in the middle because "oh, run-time limit has been reached, tune in next week!"
I also feel like a lot of writers on here misuse it in place of actual cliffhangers. Like, ending in the middle of dialogue because you simply slashed your DOC in half is NOT a cliffhanger.
I suppose if the demo likes it then it is certainly a smart tactic. But, yeah, that's why I related it to cutting creativity- Just for me, though. Definitely not a universal issue.