Trumpy it sounds like we all use the same methods.
One thing for us is there is a large difference between an emergency generator and standby or optional generators.
If a generator is classified as a buildings emergency generator all equipment connected to it must be for emergency's.
"Emergency systems are those systems legally required and classed as emergency by municipal, state, federal, or other codes, or by any governmental agency having jurisdiction."
This means entirely separate raceways, panels, electric rooms etc.
No adding a circuit for someones PC so they can check out ECN. (Sorry Bill
In my area they will let us order a genset with two or more main breakers on it one for the separated emergency loads and the others for optional loads.