I disagree. Speed at scale and scalability are the same thing, but speed and scalability most certainly aren't. A server that performs really well on a single

I disagree. Speed at scale and scalability are the same thing, but speed and scalability most certainly aren't. A server that performs really well on a single request, but slows down as requests are added would be considered 'fast', but not 'fast at scale'. Yes, there are plenty of instances in which this is the case, and most notably, this is a very common affliction with databases. Also, even in scenarios where you can add more web servers to an application stack, you can't necessarily add more database instances, so you scale those UP instead of OUT. In summary, the statements made in the article are true, but yours aren't really. In the case of web servers, yeah, they're almost the same thing. In the case of other things, they're generally not.