ITA with the above. I did mine last night and will be posting pics soon. I didn't have any problems getting them in. To set, I made sure each section was dripping wet and smoothed with a small-tooth comb before I attached the hook. And I twisted not only the roots but the entire length of the hair to keep the strands together. This prevented any snagging while pulling thru.
Now, I did have about 3 or 4 strands to get caught on a curlformer because there was a snag in the opening. The hairs came out while I was removing the curlformer (and rushing) so after that one I made sure I followed the removing directions (both hands and slowly) and I didn't lose any more. So, definitely check and make sure there aren't any snags on the curlformer itself.
OP, you are definitely right - if anyone feels like they are pulling too hard or their hair is snagging, then yes, something is wrong and no one should proceed until they can figure out what it is. Its not worth ripping your hair out