Your clarifications are fine, but I do find it to be a bit of an uncharitable reading of what I wrote, because it seems to be far less wrong than you make it out to be, if we're to believe wasoxygen.

However, the point that mattered most to what I was trying to say (point 5) turns out to be completely wrong, so it sounds like the power consumption point made in the article only applies to Bitcoin (or other similar blockchain use cases), and not blockchains in general.

I still think a lot of the other points made in the article are valid. Mainly the idea that a blockchain can't replace external human validation, since a blockchain can only verify that records have not been tampered with after the fact, but can't verify that the input records are correct in the first place. For example in the case of land changing hands, the blockchain can't verify whether it really did or not, it has to be told.

Instead of saying a blockchain is a glorified database, maybe it's more accurate to say it's a database with an elaborate checksum? A checksum can only check that data hasn't changed since the checksum was calculated, not whether or not the input information is correct.

There are also further trade-offs which do come at a cost (of course that applies to any technology);

- The security increases with the number of copies of the block chain out there, but since you need the entire chain to be copied it can be extremely storage intensive. Imagine if you wanted to use a block chain for a stock exchange; the number of transactions per day is enormous.

- Keeping all of these copies in sync costs a lot in terms of data traffic, which also creates latency. In fact, all the hashing, even if it's not quite as bad as I thought, will create latency as well. In a time where some companies move physically close to stock exchanges in order to have shorter latency over their (already speed of light) fibre, this is not a minor concern.

I think it's safe to say it's not "effectively zero cost", but it could be an acceptable cost for some applications. I also think it's safe to say there are many applications it would not be a good fit for.