We have incubated in small foam hovobator. using the turner, small end of egg down. the extra turning they are talking about is spinning the egg clockwise or counter clockwise
in the turner. Usually a 1/4 quarter turn.
So not only do the eggs go back and forth in the Turner, but you also spin them one quarter 3 or 4 times a day. The extra turning/spinning is what they say increase the
hatch rate.
Our Hovobater was old, and we had to switch from it because the thermostat became unreliable. We would come home and look and our eggs were at 102 or to low. Red
ring of death was commonplace for us. That is when we thought we could use it as a hatcher, and it burned our little chicky's head.
I would love to have a nice incubator, one of those that are water cooled if it gets too hot. but we just cant afford anything like that right now. This year My DH built a non
turning incubator from a cabinet we used information from this website to figure out how to install thermostat, and lights,.
Good luck