I got seriously contradicted on another thread when I said this. Thank you.
I have too!
Humidity needs to be between 25% and 55%. Temperatures need to be within 1%. Many focus a lot on humidity when it is really not that important.
The moisture that is on a chick that is not egg goo will not make a chick stick in the egg. Egg yolk is like a glue so if it in the egg at hatch, the chick will often stick. Temperatures out of range will make the chick not absorb the yolk along with several other things, like flock health, shipping stress and inbreeding.
To get back to Heritage, here is a picture of the SG Dorkings I hatched: