Not necessarily. Heroku claims that a global request queue is hard to scale, and therefore they switched to random load balancing. The comment above shows that

Not necessarily. Heroku claims that a global request queue is hard to scale, and therefore they switched to random load balancing. The comment above shows that a global request queue is not necessary. Lets say that minimum-of-n scales up to 10 dynos. If your application requires 40 dynos, you can have one front load balancer which dispatches the requests to 4 back load balancers, each of which has 10 dynos assigned to them on which they perform min-of-10 routing. This gives you routing that's almost as good as min-of-40 but it scales up nonetheless.