[markov_twain]

Heroku apps at the very least sit behind the heroku router, which I would assume is in the same datacenter. If the information in this quora answer http://www.quora.com/Scalability/How-does-Heroku-work is still valid, your app is also behind a front-facing nginx reverse-proxy.

I'm not sure that actually means it's handling slow-clients, though.

[nifoc]

I think the important part is that the reverse-proxy should buffer the request, but I can't find anything about wether or not the Heroku router does this.