That is because it does not actually take control away from you with any sticky/magnetic spots. A lot of scrolljack presentations have a really laggy pagination that is somehow about as precise as fast rewinding your DVR was back in 2011.
Yes, that's a sure way to make it bad. I don't think it's given (as a sibling comment to yours suggests) that simply not doing that is sufficient for any other scroll manipulation being fine though.
The intention's always good, I think, it just rarely is as nice as the author felt it would be.
