I would not personally remove the whole shell!!!
I’ve had to step in and assist quite a few times, and I feel like it is really important to let them push their own way out- even if you need to open the shell quite a bit and let them finish the job.
I remove enough of the shell to give them space to do so, if I must intervene.
I prefer coconut oil to moisten the membrane, I use qtips and slather the membrane first on the outside, and then “roll” the swab and oil under the membrane as well.
As long as there are no veins, I also open the membrane a bit more as I go.
Olive oil also can work if you don’t have coconut oil. I’d go next to Vaseline if that was your only other option.
Any “lubricant” will need to be re applied if progress remains slow- coconut oil usually “lasts” 8-12 hours depending on humidity and how quickly you can work when the egg is out of the ‘bator/ how quickly you bator comes back to proper humidity after opening it.
I can’t speak to the others because I’ve no personal experience w them.
They will be a bit greasy for a minute, but I’d rather have a greasy baby alive, than one that died trying to get out!
I also open the entire air cell end, and not down the shell.
These are ducks- the last eggs that showed signs of life but had not externally pipped from a big run from last summer.
I had to open the shell, peel it back in the air cell area, lube the membrane, carefully work everything back.
They did get rolled around by the earlier hatchers, so.... I’m not sure if they couldn’t get in the right position due to being bowling balls, or?
The one on the right still had a vein I didn’t see until I “lubed” the membrane (you can see the red, that is why I start by lubing the outside so you can see any small veins that may still be there before you open the membrane up)
All three of those babies are happy, healthy adults now