Whitepaper?
Sounds OKish, but probably depends on the ark central authority who can do an exit ones running away with funds and perhaps knows transaction linkability since they do the CoinJoin.
It reads like the only main downside is the cost for publishing a hash every 10 minutes and the need to wait 10 minutes for finality. Anyhow, that is my 5 minut read impression 
.
What is your view on Ark @trab ?
This is excellent. Many diagrams Deep Dive
I think the main downside is this actually:
Ark service providers, can in theory, double-spend their pool transactions while they sit on mempool. However, in the meantime, recipients of the pool can pay lightning invoices with their incoming zero-conf vtxos, so itâs a footgun for the service operator to double spend in this case.
A transfer schedule from a sender to a receiver is atomic in nature. ASPs cannot redeem sendersâ vtxos if they double-spend recepientsâ vtxos under the mutually agreed coinjoin transaction id.
Iâm on board with anyone that is realistic about why Lightning sucks, because it truly does. People get so obsessed with driving adoption at all costs (they want number go up) that they forget that good UX will naturally drive adoption on its own!
I think he correctly identified the main issues with Lightning and is solving it in a really clever way. And just like Lightning, it seems like others could use a similar system for their layer 2 as well, right?
With the Lightning Network you still have to worry about onboarding, offboarding, fees, channel capacity, channel liquidity, routing, watchtowers, being online, âFlood & Lootâ, etc. LN definitely adds to Bitcoinâs scalability, but itâs not a panacea. Some L1s are far less complex, easier to use, cheaper (e.g. feeless), and donât have the same caveats that LN comes with