The biggest issue is that these incredibly short block intervals will lead to tons and tons of orphaned blocks. Network speed/latency will become a pool's limiting factor, not hashrate.
So you are saying that he is lying when he says:
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still keeping the coin safe from stale blocks and competing chains.
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still keeping the coin safe from stale blocks and competing chains.
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I'm saying it's of limited bearing. A better claim would be that it "keeps the coin as safe from stale blocks and competing chains as possible." The blocks still need to propagate, there will still be competing chains, and because of the short block time, network latency becomes a big overhead.
EDIT: Sorry my first statement; it was made rather quickly after only glancing through the entry, but my thought stands.
