While good for some dynos, it can be poor for others. Any system that handles singe requests serially is an irresponsible choice for anyone who might bother to

While good for some dynos, it can be poor for others. Any system that handles singe requests serially is an irresponsible choice for anyone who might bother to look into queuing theory enough to blame the router but not be willing to blame their application server. There are systems that do benefit from other kinds of routing but there is very little margin to favor non-concurrent request handling in mostly state-less components like web servers. There are lots of responses on the web that take a much deeper look at the heroku router if you care to search. The conclusion is not so clear that Heroku is doing it wrong.