TBG-162

Will the Deceptive Segwit2X Attack Succeed?

October 27, 2017 · YouTube · All episodes
TBG-162 cover frame

Where the panel landed

Would SegWit2X succeed as a technical, economic, hash-power, and naming attack on Bitcoin, or would the existing Bitcoin ecosystem absorb it as another hard fork?

Thomas framed SegWit2X as a coordinated corporate takeover, while Jimmy Song and Tone Vays were less convinced that the attack would succeed. Jimmy repeatedly argued that replay risk, SPV confusion, and naming games were solvable or survivable if users, wallets, and exchanges acted carefully. Tone agreed the attempt was serious and criticized companies like Coinbase, Zappo, and BitGo, but saw the 2X side as technically weak, economically vulnerable, and unlikely to overcome Bitcoin’s social defense.

PessimisticMixedOptimistic
The panel expected Bitcoin to survive SegWit2X, but the episode was dominated by preparation, worst-case planning, custody risk, and concern over corporate deception.

What they were watching

Bitcoin was discussed near all-time highs, with Tone saying the market was not scared and that he remained bullish into the 6,000 to 7,500 dollar range. He expected another top later in the year and a more sustained selloff afterward, but did not think the yearly top had necessarily arrived. On the fork itself, Jimmy expected the price to go up after the fork because successful defense would make Bitcoin more anti-fragile, while Tone and Jeffrey expected a sell-the-news decline from higher levels.

SegWit2X technical attack

The show opened by framing SegWit2X as a technical attack: a hard fork without strong replay protection, using the same address space and potentially confusing SPV wallets. Jimmy argued that users and wallets had practical defenses, including tainted UTXOs, faucets, locktime methods, and SPV checks to detect which chain they were on.

Wallets forced onto defense

Tone and Jimmy agreed that the hard fork forced wallet developers to spend time on defensive features rather than more productive upgrades. Jimmy said coin control, locktime options, node selection, and expert-mode tooling would make wallets more resilient not only for this fork but for future ones.

Economic attack and Roger’s bet

The panel discussed large holders selling or betting real Bitcoin against SegWit2X coins, including Roger Ver’s public bet with Bitcoin supporters. Tone called the bet a financial no-brainer for anyone willing to publicly expose their coins, while Jimmy argued that conviction among Bitcoin holders made a sustained economic attack unlikely.

Holders as economic defense

Jimmy emphasized that Bitcoin’s economic anti-fragility depends on holders who believe in the original chain and refuse to sell. He argued that the 2X side appeared less committed and more conditional, while Core-side supporters had stronger conviction and would not be easily shaken out.

Hash power and longest chain

Thomas raised the risk that SegWit2X could claim the most accumulated difficulty and fastest blocks if enough miners followed the New York Agreement. Jimmy doubted the 90 percent miner claim, expected many miners to follow profitability, and argued that even a temporary slowdown on the original chain would not matter much for Bitcoin as a store of value.

Nodes and signaling disagreement

Tone urged users to run updated Bitcoin Core nodes as a public and practical rejection of 2X. Jimmy disagreed that public node counts were a decisive signal because they can be Sybil attacked, arguing instead that nodes are primarily for personal verification and privacy.

Naming and deception

The final issue focused on Coinbase, Zappo, Gemini, and Bitcoin.com potentially labeling SegWit2X as Bitcoin. Jimmy called it a branding and legal-risk problem rather than a protocol-level threat, while Tone and Thomas warned that new users could be deceived if major companies deliberately renamed the coins.

Social anti-fragility

Jimmy argued that companies attempting to redefine Bitcoin would face the social immune system of Bitcoin holders, developers, and educators. Tone agreed that public pressure, withdrawals, boycotts, and reputational consequences could matter, comparing it to earlier user backlash when Apple removed Bitcoin wallets.

There are ways to protect against replay attacks.— Jimmy Song
everyone is absolutely terrified of moving their Bitcoin— Tone Vays
right now what the network needs is immunization— Jimmy Song
This thing is not going to come close to succeeding.— Tone Vays
The name Bitcoin will mean what the community says it means, not what you say it means.— Jimmy Song
I believe Bitcoin is a great thing and worth fighting for— Thomas Hunt

Story of the Week

SegWit2X becomes the corporate takeover test

The entire episode was structured as a special examination of SegWit2X as a multi-front attack on Bitcoin. Thomas divided it into technical, economic, longest-chain, and deceptive naming attacks, each centered on a different way the New York Agreement signers might confuse users or seize the Bitcoin label. Jimmy pushed back against the strongest version of the threat, arguing that wallets, exchanges, UTXO tainting, and social coordination could handle much of it. Tone treated the same event as a serious but clumsy corporate attempt to turn Bitcoin into a PayPal-style system rather than a decentralized protocol.

On November 15th, the corporate takeover of Bitcoin begins.— Thomas Hunt
SegWit2X arrived as a takeover, a fork, a branding exercise, and a stress test; Bitcoin answered mostly by making everyone check their wallets.
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