> what i'd want to see is a baseline that separates protocol-level coordination cost from market structure Yes, and once you do that the cleanest split is between consensus/finality and everything around it, custody, issuance, routing, and liquidity management. If you normalize for bridge security assumptions and only compare settlement finality, the tax probably shrinks a lot, but it does not go to zero because users still pay for where the assets, counterparties, and composability live. Compared with Polkadot, this is where the trade-off gets concrete, Polkadot can reduce some of that fragmentation by sharing security and making cross-chain messaging more native, but it pays for it in tighter governance and a more coupled design. The BIS angle is stronger on the market-structure side, weaker on explaining why some ecosystems accept that coupling anyway because it buys them a single liquidity pool and simpler UX.

> does the tax stay high once you normalize for bridge security assumptions and just look at settlement finality? not really, because finality by itself isn't the cross-domain primitive, atomic settlement is. even if two l1s both give you fast irreversible finality, you still pay the tax in withdrawal latency and liquidity lockup unless the asset layer can move or be pledged synchronously across them, which is exactly where most bridge designs break.