"Centralization of mining due to slow propagation with bigger blocks" is mostly a strawman argument.
Even if the blocksize went up to 8MB with no increases in Internet speed,
you're talking about 8 seconds difference between an 8mbit connection and
a 16mbit connection. Compare to the 600 seconds required to solve a block
and you get 8/600 = .0133~. So that's a 1.3% advantage to the faster
miner. Quite dubious to say that would be a crushing competitive advantage
given that there are other factors involved in mining costs such as electricity,
gear, and operations.
Sry, I can't follow your numbers there with regards to block propagation. But mining centralization has already largely happened because of the economics of Bitcoin mining.
Mining centralization already happened but small blockers are afraid that the geographic area or region with fastest internet speeds will become the only
place mining will be competitive if blocks get big. But I'm not buying their argument.
Big miners just need a server located somewhere with high bandwidth connection to as much of the globe as possible. This server sends work (tiny amounts of data regardless of block size) to the their mine in the outback. Or they, or anyone else, can join a pool.
As far as the numbers, there's 8 bits in one byte. Therefore, a difference of 8 megabits in speed is one megabyte per second.
If block size is 8 MB, that's 8 seconds. Yet it takes 10 minutes to solve a block so 8/600.
It's not like every miner has 5891 connections. They send to as many nodes as they can and those nodes send to as many as they can and so on. It's sort of like grass fire.
That is true. But to claim consensus when the lines haven't moved is a bit weird and, in my view, quite problematic. A more honest approach would be to admit/accept that consensus could not be reached but that this particular group has decided to move forward with an agreed upon set of solutions.
The lines have not moved a bit? Are you even sure about that? The roadmap for 2016 was signed by several people.
"[M]oved a bit"? Anyhew, this is roughly what I meant:
Three out of the five Core committers, did not even sign on to the Core road map.