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by scotty79 2355 days ago
I wrote down my understanding of bitcoin and influence of the block size as a train analogy. Here it is for you to make fun of:

Imagine there’s a train line. Trains go at regular intervals and have fixed number of seats.

Operator of the train line gradually issues unfalsifiable coins which there will eventually be specific number of and not one more. You can carry any amount of coins while you ride the train. People started to find them valuable so you can buy them before departure and sell on arrival.

Tickets for the train are auctioned for coins. Only the people who bid most can ride the next train. You can even bid 0 coins and get on the next train for free if not enough people outbid you.

Making train go is the cheap and easy part. What’s expensive is securing it from robbers that could disrupt the service and tank the value of the coins. Operator outsources this task to Miners&co. They make the train secure proportionally to the amount of real money they spend. To compensate them operator pays them with freshly minted coins for securing each train. Since operator intends to emit a predetermined number of coins in total it has to periodically lower Miners&co reward for each train secured.

There’s a risk that the price of the coins won’t grow fast enough and securing trains will get less and less profitable for Miners&co and they will secure trains less and less until train line falls victim to the robbers.

To create a second source of income for Miners&co operator gives them the fees that people bid to be on the next train. Operator is not sure if it will suffice but that’s the best he could come up with.

There’s a surge in coin price and people start to ride trains like mad to sell their coins at places where there are buyers. People outbid themselves to be on the next train to the point that travel becomes uneconomical for casual travelers. Some of the travelers say: “Make the trains larger so we can all fit in for cheap”. Operator could do that at no cost, because running trains of any size is the cheap and easy part.

If the operator decides to make the trains larger he is lowering the amount of coins that people will have to pay to travel and thus lowers income of Miners&co and thus lower the incentive to maintain high security of the trains. Incentive that the operator already wasn’t sure was sufficient to keep Miners&co interested forever. Operator would be taking away profitability from Miners&co and make them worry that he could just take away more of their profitability in the future on a whim. What’s next? Even less fees? Maybe no base reward for securing trains? Maybe fixed or increasing reward that makes coins not scarce anymore and thus less valuable in terms of real money?

If the operator decides to not make the trains larger, he makes the casual travellers that like to travel often with a small amount of coins unhappy, to the point of using other trains and coins altogether. But the operator keeps Miners&co profitable and communicate to them that he doesn’t intend to change any core rules in a way that negatively affects their profitability

Travellers say, if the operator makes the trains larger, and as a result makes travel faster and fees lower then more people will travel and coin will become more valuable offsetting any loss of profitability that Miners&co suffers as a result of larger trains.

But the operator knows that what makes his coins valuable is not that his trains are fast, or large or cheap or used often. What makes coins valuable is that they are in strictly limited supply and that the trains will operate forever secured strongly enough to never get disrupted by robbers. So the operator chooses not to make trains larger because Miners&co profitability and trust must be considered before anything else because security they provide is one of the two necessary things for the coins to be valuable.

Some people are very upset and they make their own train line and coins (which they give to people that own operators coins). Miners&co prefers to secure operators trains more and the new larger ones less. Price of operators coins doesn’t suffer and follows usual curves it previously followed around moments of high interest. Operator can infer from that that he chose correctly.

Will the operator be able to keep trains running safely forever? Nobody knows, because outside of well modeled problems, nobody knows what the future will be. And this train line is the first of its kind. I you think it’s doomed you are free to ride any other. There are so many now that do various things differently. Choose wisely because many of them already died abandoned by Miners&co.

1 comments

> I wrote down my understanding of bitcoin and influence of the block size as a train analogy. Here it is for you to make fun of:

You and people like you think I am making fun of you because you are flatly wrong about so many things in the space, and seem to have no idea that you have been conned. I'm not making fun of you at all, I'm pointing out the ways in which you are wrong.

> You can even bid 0 coins and get on the next train for free if not enough people outbid you.

Wrong, you can have an empty block with bids in the mempool below the threshold which miners are willing to incorporate, and they still don't get into the block. You don't magically get into the block on a zero bid just because it's not full.

> Making train go is the cheap and easy part. What’s expensive is securing it from robbers that could disrupt the service and tank the value of the coins.

Wrong, on the security front we have proof of work output in the ~800k USD equivalent every hour range, on the actual functionality front, the primary chain has been sabotaged to be so dysfunctional it barely matches a fax machine in raw throughput, this is equivalent to a depleted uranium armoured rail car with a convoy of tanks as an escort, but it's only 5x5 inches and it runs on a mousewheel. Other node software not subject to the BTC sabotage runs enormously better, things like flowee the hub getting up into tens of thousands of validated transactions per second on commodity hardware, but they're so poorly adopted as to be basically unknown. In terms of deployed infrastructure, we're stuck with the 5x5 mousewheel pushcarts because of the BTC sabotage.

> Since operator intends to emit a predetermined number of coins in total it has to periodically lower Miners&co reward for each train secured.

Wrong once again, there's no "has to" about it, the emission schedule could have been a completely linear flat rate. It was chosen to be a steeply declining curve to bomb the project if it turns out not to actually be a useful service for which people are actually willing to pay, that is, uptake and increased usage is intended to make up for the lost value of the decreasing block reward. The steeply declining curve ensures that the interests of all the maintainers of the Bitcoin network are aligned, as only an insane fool would ever try and actually sabotage the network to be dysfunctional knowing that this would be the inevitable fate if they did.

The BTC sabotage turns this on its head and assumes that instead scaling should be crippled on purpose, and an artificial limit should be forcibly imposed in order that the supply quota can hopefully address the diminishing block reward over time.

This, like basically everything else in BTC, is extremely, indescribably stupid. The inevitable fate remains the inevitable fate for the aforementioned stupidity.

> There’s a risk that the price of the coins won’t grow fast enough and securing trains will get less and less profitable for Miners&co and they will secure trains less and less until train line falls victim to the robbers.

Wrong, because the price of coins is not the only variable that dictates how much security is invested into each block. BTC simply attempts to force it to be so for no good reason and this is transparent sabotage.

> Operator could do that at no cost, because running trains of any size is the cheap and easy part.

Wrong. Operator alone does not get to choose to do that period, a block limit of x does not imply a block floor of x, miners can and do still choose to emit blocks significantly below the block ceiling.

The entire rest of your analogy collapses because it based upon these incorrect assumptions.