> "these sidechains are terrible" on Monday and then "these sidechains are so good they will replace the mainchain" on Tuesday

Your premise is that a sidechain might come to dominate bitcoin, and that this would be better than an altcoin dominating bitcoin. Did I misunderstand you? Not quite sure why you're balking at me simply confirming your premise.

> sidechains cannot exist without their mainchain .. imagine .. a zcash sidechain, and someone claims they deposited 1000 BTC

A sidechain could stop supporting deposits from or withdrawals to bitcoin and completely break any relationship with the main chain. I agree this is not as sure of a thing as starting with an altcoin (which of course never has that kind of relationship with bitcoin). So I do think there are some merits to sidechains in your scenario. However, I don't think its quite accurate to say it completely solves the problem (of a less-secure altcoin becoming dominant).

Your anecdote about not running a full node is amusing, and I've often found myself in that position. I certainly agree different people are different and so different trade offs can be better for different people. However, the question is: what tradeoffs does a largeblock sidechain do better than both eg Visa and lightning? 
>Wouldn't life be better, if we Bitcoiners could easily sweep those fiat transactions into *some* part of the BTC universe? (For example, a family of largeblock sidechains). To me the answer is clearly yes.
I guess its not as clear to me. We agree it wouldn't significantly burden Bitcoin-only nodes, but not being a burden is not a sufficient reason to do something, only reason to not prevent it. But what are the benefits to a user of that chain? Slightly lower fees than main bitcoin? More decentralization than Visa or Venmo? Doesn't lightning already do better on both accounts? 


On Tue, Mar 1, 2022 at 6:00 PM Paul Sztorc <truthcoin@gmail.com> wrote:
On 3/1/2022 12:39 AM, Billy Tetrud wrote:
This entire issue is avoided completely, if all the chains --decentralized and centralized-- and in the same monetary unit. Then, the monetary network effects never interfere, and the decentralized chain is always guaranteed to exist.
It sounds like what you're saying is that without side chains, everyone might switch entirely to some altcoin and bitcoin will basically die. And at that point, the insecurity of that coin people switched to can be heavily exploited by some attacker(s). Is that right?
Yes, precisely.

    

      

        

          
Its an interesting thought experiment. However, it leads me to wonder: if a sidechain gets so popular that it dominates the main chain, why would people keep that main chain around at all?

        

      

    

    
For some reason, this is a very popular question. I suppose if you believe in "one size fits all" chain philosophy (see comment below), it makes sense to say "these sidechains are terrible" on Monday and then "these sidechains are so good they will replace the mainchain" on Tuesday.

In any event, sidechains cannot exist without their mainchain (as I see it). For example, imagine that you are on a zcash sidechain, and someone claims they deposited 1000 BTC, from Bitcoin Core into this sidechain? Do you give them 1000 z-BTC, or not? Without the mainchain, 
you can't tell.

If you run the Bip300 DriveNet demo software (drivechain.info/releases), you will see for yourself: the test-sidechains are absolutely inert, UNTIL they have rpc access to the mainchain. (Exactly the same way that a LN node needs a Bitcoin Core node.)




    

      

        

          
> someone is actually in the wrong, if they proactively censor an experiment of any type. If a creator is willing to stand behind something, then it should be tried.

        

        

          
> it makes no difference if users have their funds stolen from a centralized Solana contract or from a bip300 centralized bit-Solana sidechain. I don't see why the tears shed would be any different.

        

        

          
I agree with you. My point was not that we should stop anyone from doing this. My point was only that we shouldn't advocate for ideas we think aren't good. You were advocating for a "largeblock sidechain", and unless you have good reasons to think that is an idea likely to succeed and want to share them with us, then you shouldn't be advocating for that. But certainly if someone *does* think so and has their own reasons, I wouldn't want to censor or stop them. But I wouldn't advocate for them to do it unless their ideas were convincing to me, because I know enough to know the dangers of large block blockchains. 

        

      

    

    
Yes, I strongly agree, that we should only advocate for ideas we believe in.

I do not believe in naive layer1 largeblockerism. But I do believe in sidechain largeblockism.

Something funny once happened to me when I was on a Bitcoin conference panel*. There were three people: myself, a Blockstream person, and an (ex)BitPay person. The first two of us, were valiantly defending the small block position. I gave my usual speech: that node costs must remain low, so that people can run full nodes. The largeblocker mentioned that they ran many nodes (including BCH nodes etc) and didn't mind the cost, so I disclosed --in a good-natured way-- that I do not even run a BTC full node myself (out of choice). Thus, I was yammering about software I wasn't even running, I had no skin in the game! Lo and behold -- my Blockstream smallblocker ally-on-the-panel, immediately admitted to everyone that he did not run a full node either. The only node-runner was the largeblocker. The audience found this very amusing (as did I).

We smallblockers, justified our sinful nodeless behavior, as follows (paraphrasing): we receive BTC mainly from people that we know (and have a long-term relationship with); our receipts are not time sensitive; we are not paid in BTC that often; if payments turned out to be forged we would have enormous recourse against our counterparties; etc.

We did not run full nodes, because we did not need to draw on the blockchain's powers, **for those transactions**.

Which is my point: people are different, and transactions are different. I make many transactions today, with VISA or Venmo. These are not censorship-resistant, but somehow I survive the month, without bursting into flames.

Wouldn't life be better, if we Bitcoiners could easily sweep those fiat transactions into *some* part of the BTC universe? (For example, a family of largeblock sidechains). To me the answer is clearly yes.

Unlike layer1-largeblockism, no one running Bitcoin Core ever needs to see these 'btc' transactions (the same as we don't see them today, on account of them not existing at all); they do not burden Bitcoin Core full nodes. Hence why it seems like a good idea to me.

An SPV-wallet-of-a-largeblock-sidechain, is of course, a *disgrace* compared to a full-node-of-smallblock-mainchain-Bitcoin-Core. But, it is emphatically superior to Venmo / VISA or even "custodial LN". And certainly superior to nothing.

Paul

* https://www.youtube.com/watch?v=V3cvH2eWqfU