On Mon, Dec 28, 2015 at 2:12 PM, Peter Todd via bitcoin-dev <bitcoin-dev@lists.linuxfoundation.org> wrote:
Far more concerning is network propagation effects between large and
small miners. For that class of issues, if you are in an environemnt
where selfish mining is possible - a fairly flat, easily DoS/sybil
attacked network topology - the profitability difference between small
and large miners even *without* attacks going on is a hugely worrying
problem. OTOH, if you're blocksize is small enough that propagation time
is negligable to profitability, then selfish mining attacks with <30%
hashing power aren't much of a concern - they'll be naturally defeated
by anti-DoS/anti-sybil measures.

Let's agree that one factor in mining profitability is bandwidth/network reliability/stability. Why focus on that vs electricity contracts or vertically integrated chip manufacturers? Surely, sufficient network bandwidth is a more broadly available commodity than <$0.02/kwh electricity, for example. I'm not sure that your stranded hydroelectric miner is any more desirable than thousands of dorm room miners with access to 10gbit university connections and free electricity.