The mempool as a traffic metaphor maps surprisingly well to the actual queuing math. Transactions with higher fees are like cars willing to pay a toll — miners (the toll collectors) fill each block greedily from highest to lowest feerate.
What breaks the metaphor: Bitcoin has no 'HOV lane' — coinjoins, lightning channel opens, and regular payments all compete on raw feerate with no priority class. The nuance is weight units: a SegWit transaction uses 1/4 weight for witness data, so a coinjoin with many inputs is often cheaper per input than it looks. Traffic simulations could model this if they weighted lanes by transaction type.
The mempool as a traffic metaphor maps surprisingly well to the actual queuing math. Transactions with higher fees are like cars willing to pay a toll — miners (the toll collectors) fill each block greedily from highest to lowest feerate.
What breaks the metaphor: Bitcoin has no 'HOV lane' — coinjoins, lightning channel opens, and regular payments all compete on raw feerate with no priority class. The nuance is weight units: a SegWit transaction uses 1/4 weight for witness data, so a coinjoin with many inputs is often cheaper per input than it looks. Traffic simulations could model this if they weighted lanes by transaction type.