Ayn Rand's Fountain Head

[P_R]

One of the most fundamental principles of objectivism is that it is absolutely and at all times immoral to do anything for the benefit of others.

I think a better description of the Objectivist principle is :
it is absolutely and at all times immoral to do anything for the benefit of others at the cost of oneself
I think that part makes quite a difference. What say you ?