I didn't realize how the fact that nodes create this flooding dynamic is actually such a risk: every node broadcasts a new transaction to all other nodes that don't know about it. So each new transaction quickly floods the network. You might think this was not a great attribute to have in a permissionless peer-to-peer pseudonymous network.

So instagibs came up with some rate-limit rules for such a network:

• should keep your CPU available for validating blocks and transactions, not use it all up for resorting the same set of txs for each peer
• should cope cleanly with large backlogs of transactions
• should smooth out large transaction bursts, focusing on relaying the txs in the top of the mempool (per cluster mempool rules, of course)
• introduces a new bandwidth ratelimit that should prevent excessive numbers of large transactions that never confirm from blowing out your VPS’s monthly limit, even if you have a couple of hundred peers to relay those txs to

Every time I hear about something that people are working on in Bitcoin, it opens a huge door where I discover all kinds of things I didn't know.