There's some false information in your post. I have read where other people mention that they have blunt ends without doing any rolling or crocheting.
not shure i understand what you mean or even if we are talking about same thing. im talking about shortening dreads if you think their too long, and not ending up with that scissor cut look.
I trim mine from time to time if one annoys me, tidys em up, I like nonuniform shapes and sizes, but I'm not a fan of wild loose bits blowing around, if your dreads are locked up you can cut and they'll blunt, if they're not locked up the ends are likely to fray.
i have two dreads right in my face that were all whispy, but they kept tickling my nose and blowing around getting in my eyes,... so i played with them a lot just at the tips. i was rubbing the tips between my fingers and they curled up and blunted, yeah. so now they don't tickle my nose because they aren't wispy anymore. those are the only ones with blunt tips. i didn't do any crochet or trimming, just played with them.