[tor-relays] About relay size

[grarpamp]

> Larger, faster relays help clients achieve low-latency, high bandwidth
> connections.

This may depend? Do we have a graph of actual headroom / saturation
in the network of boxes versus consensus weight versus max box speed?
Does weight back off below historically sensed saturation levels?
Because seems even the fastest box would become high latency low
bandwidth upon saturation, and a path through three 40Mbit boxes
that are all 25% loaded might provide better performance than through
a single saturated gig box anywhere in path.