[nullc]

> Even if fewer nodes are involved with each transaction, the LN seems to rely on a lot of message passing; beyond what a simple broadcast on the base layer requires.

Today sending a transaction communicates 10 messages for each of ~100k nodes in the network. Once its confirmed, that transaction will additionally be sent once to every new host to join the network, forever.

Lightning sends a couple of messages back and forth among the nodes directly involved in the transaction... maybe 4. (The average shortest path length is about 2.8 currently).

So the marginal communication cost for a transaction is literally hundreds of thousands times lower-- even ignoring the cost to future nodes joining the network-- and this advantage grows as the number of nodes increases.