Phoenix's are coming and going too, and his behaviour is normal too. I wish I knew what was going on. I assume the colour change is due to variable oxygenation not just e.g. mood and he's dealing with some health challenge without other visible symptom. Llyn's whole comb is looking distinctly more grey and he appears unwell, though there's nothing wrong with his appetiteHenry had dark points on his comb late this evening but is behaving normally.

I limit to what the hen in question can cover comfortably, with a min of 4 and max of 9. If they're home grown eggs, I like to include an egg from each of the hens who does not yet have offspring. In these cases, a failure to hatch means hen(s) still haven't passed on their genes, so I have to hope they survive another year to do so. If they're purchased hatching eggs, they usually come in 6s. In these cases it's easier if only a proportion hatch, as ID-ing is hard when there are identical birds running with an otherwise heterogenous flock.It's funny reading the above about hatch rates. I didn't worry about it. I limited the eggs, usually six, and hoped the would hatch three.
The upside to one or more not hatching is that the broody stays on the nest another day or two and the hatched chicks get to use what nature provides for their first few days, ie the absorbed yolk, before food starts passing through their gut. When I was a novice I thought they needed food and water straight away. Now I know better.