As per my understanding, for a bean there is always one home interface reference. Whenever the client wants to get the Component reference. Home reference is used and hence the client get a customized bean (stateful) for his/her use. While going through chpter 5 entity bean intro, Kathy has mentioned that the Home can aswell hold business methods for the bean. Some how I have started thinking that the business methods in home will start acting as a static methods. i.e. methods bound to class kind of scenario. With this assumption I think if my business method is looking for some specific info in bean then this kind of call will be confusing.
Home business methods are for business methods that are not pertaining to a single entity (row in database) for batch processing of entities If your business method is looking for some specific info in bean then it wont be a good candidate for a home business method.
I dont know how it is actually implementedbut if I were to make my own ejb container I would make the conatiner generated class which actually implemenbts the home interface inside the conatiner a singleton.
My knowledge is based on my imagination and what little I have read.