> or some transactions could be moved to “sidechains” as proposed in systems like the Bitcoin Lightning Network. But the Lightning Network is useful only for a ledger that is denominated in Bitcoin, and we still have to deal with the “central” Bitcoin blockchain, whose size is likely to continue to increase despite the addition of various “sidechain” mechanisms.

This is incorrect for multiple reasons.

> "Takes over 10 minutes to “commit” a transaction"

Incorrect. Average wait time would be less than 5 minutes.

> "Turning your Bitcoins into cold hard cash denominated in the currency of your choice is perhaps the cryptocurrency’s biggest problem"

It is author's world view based on pre-bitcoin times that cold hard cash is better. It can be said that turning cash to bitcoins is fiat's biggest problem.

>"moving money between ledgers actually involves integrating with those ugly legacy systems"

Assets on different blockchains can be swapped using various methods and does not need third parties.

> "there are far more efficient distributed consensus algorithms than this which don’t involve a proof of work."

Author gives the example of Interledger and SCP. Without proof-of-work origin of money will always be controversial. Both Ripple and SCP create money out of thin air.

>a very cool feature I will acknowledge exists and give a quick hat tip to Ethereum

There is NOTHING that ethereum can do that you can't do with bitcoin.

> Bitcoin-NG (paper), a protocol that inverts the ordering of Bitcoin consensus: a miner is first elected leader by winning the proof-of-work “lottery” by mining a “key block”, and then once elected leader becomes a transaction broker who can mint “micro-blocks” via digital signature until the next leader is elected.

Many problems linked https://www.reddit.com/r/Bitcoin/comments/3or365/bitcoinng_p...

I did not read last 3 paras. The author is damn right that Blockchains are world's shittiest databases and should not be used so.

In my personal understanding of what blockchain is, the author didn't mention it as a DMMS(Dynamic membership multiparty signature). This has been explained in the sidechains whitepaper, which most people do not read due to another myth that the employees of a private company 'blockstream' are majority of Bitcoin Core devs. Anyone trying to understand the blockchain should read the introduction of that paper. https://www.blockstream.com/sidechains.pdf