You have to do what your comfortable with and be comfortable with whatever the results may be. I hatch batches of ducks and chickens year round. And each year I gain more & more experience and do things slightly different based on cumulative results. This year I’ve hatched quite a few batches of call duck eggs (my own, local eggs NOT shipped). And I’ve seen that interfering as little as possible is best (for me). I have definitely had to help a few out in each batch because they are stuck and will not get out without help. But I wait as long as possible before interfering. Most of the others have hatched by the time I help. There’s NO veins by the time I help. This goes for the pointy end pips and the regular pips that get stuck zipping. I’m not comfortable with seeing blood when ducklings/chicks are hatching so I avoid messing with them to quickly. That’s just me. That’s what I’m comfortable with. If they can breathe, I leave them alone for hours & hours & hours. I’m ok with the fact that they might die if I wait to long because that’s never happened (but it is a possibility). I’d rather be safe then sorry I helped to soon. As long as they are breathing they have been ok with me waiting. Just wanted to put my experience out there in case it can help anyone else. But there’s always risk no matter what. Find what your comfortable with.