Herefordsire,
The quality of hair coat that I often mention and "good hair" for a club calf are two very different things for very different reasons.
A good haircoat is heritable, but nutrition also plays a big role in how the coat looks, it doesn't change the inherited quality or lack thereof though. The coat of a bovine is the window through which you can look to see the health status of the animal and how its nutritional needs has been met.
To completely hijack Jeanne's thread...
I know you like dark coated animals, but as a general observation (by me and a few, more much more experienced than me, long term hereford breeders here in SA), poor hair coat quality is found more often in darker coated animals than lighter red animals. Not saying there isn't exceptions to the rule or that all lighter red animals has good coats, just merely our observation after years of selecting for coat quality. Just as a final comment on hereford coat colour, ebony isn't any more breed characteristic than yellow, cherry red to yellowish red is what the original breed standards specify.