Random routing is still wayyyyy worse than intelligent routing even if you're processing multiple requests simultaneously on a single dyno (see http://rapgenius.com/1504222)
Requests will still queue, but since time spent queuing at the dyno level doesn't appear in your logs or on New Relic, you'll never know it.
I think that's one of the real tragedies under all this, and compounding the tragedy is that it's going under-discussed: the performance monitoring is incomplete. If the dyno level queue time was apparent, this issue would have become obvious much sooner.
Random routing is still wayyyyy worse than intelligent routing even if you're processing multiple requests simultaneously on a single dyno (see http://rapgenius.com/1504222)
Requests will still queue, but since time spent queuing at the dyno level doesn't appear in your logs or on New Relic, you'll never know it.