Okay but if you have somewhere in the neighborhood of three megaminers, of a scale about like one would get by Google buying deepbit, Paypal buying another, Amazon buying another, etcetera, Eligius either heaviliy sponsored by whatever coalition of bible-thumpers can add up to such scales or marginalised due to being actually trivially small in the new larger scale scheme of things, the only propagation that matters is the direct high bandwidth pipes between these superpowers. The 49% or less - the whole rest of humanity - gets a crumb from the superpowers' table less than 50% of the time and even within that demographic the bigger fish in that smaller pond can hook up directly to each other, and maybe even try to co-operate in finding sneaky ways to get more peeks faster at what the superpowers are actually working on in a given one block period, so quite possibly half or more of the 49% also are not affected by the relaying decisions of mere non-mining nodes.

Lets think for a moment of all those Jalapinos that once upon a time sounded like they could decentralise hashing power into every home. Are all those coffee-warmers going to have to be moved out from under livingroom or home-office coffeecups, co-located in data centres somewhere, if they are to be able to keep up with actually validating? They would, if they didn't actually validate, be merely rubber-stamping on behalf of someone else...

-MarkM-