What will be left for blockchain miners if even large payments will go into lightning? And on the other hand, why with a large payment to do the transaction twice, first from the blockchain to lightning then back, when you can send through the blockchain more reliably?

AMP is great, it’s been in LND since v0.13: https://docs.lightning.engineering/lightning-network-tools/lnd/amp

Tobi’s guide, which the linked article is about, seems very well done: https://tobiojuolape.hashnode.dev/a-comprehensive-guide-to-lightnings-atomic-multipath-payments-amp

…but this article is awful. It mistakes a tutorial about using a protocol (available as a feature in LND for years) for actually creating the protocol.

бессмысленно. дешевле отправить через 1 слой. во вторых кто будет отпровлять через молнию если все известно особенно узлы) смешно... и еще ... дешевле поднять стоимость биткоина в 100 раз чем рисковать этим способом.!)))