Mining pool centralization is a live systemic risk

⚠️ Time-sensitive — not re-verified since `asOf` (2026-07-22). Two load-bearing statements below describe a moving deployment state rather than a structural fact: that standing up a new pool is hard "today" because production pool software is not fully open source, and that decentralized block-template alternatives (P2Pool lineage, Stratum V2, datum-style template independence) have adoption that "remains marginal… not load-bearing yet." Present-day pool concentration shares are assumed rather than stated, and they drift too. asOf records the last verification, not the last edit — any editing since then left the date unchanged because it added no re-verification of adoption levels. Re-verify pool shares and template-decentralization adoption against a primary source before using either side's version on stage.

Concentration of block construction in a handful of mining pools remains one of Bitcoin's most serious unresolved vulnerabilities.

For (strongest version as argued): Hashing and mining are different functions: hashing is naturally decentralized because power and waste-heat opportunities are geographically dispersed, but the pools that construct blocks are few, identifiable, and jurisdictionally exposed. When a pool misbehaves or complies with transaction-selection pressure, the remedy — hashers repointing to alternatives — depends on alternatives existing; today, standing up a new pool is hard partly because production pool software is not fully open source. The 2014 episode of a single pool reaching half the network's hash rate showed the failure mode is real, and out-of-band fee channels (accelerators, direct submission deals) compound the advantage of the largest pools.

Against (strongest version as argued): The pool layer is contestable in practice: hash power has repeatedly and rapidly migrated away from pools that crossed community red lines (the 2014 pool voluntarily capped itself under exactly that pressure); new pools and decentralized block-template protocols (P2Pool lineage, Stratum V2, datum-style template independence) exist and improve; and pool concentration overstates control because pools cannot silently deviate — their blocks are public and hashers can leave within hours. Template-construction decentralization is also less powerful than claimed: profit-maximizing templates converge on the same transaction set regardless of who builds them.

Nuance: Both sides accept the hashing/pool distinction and the migration mechanism; they disagree on how fast migration works under state-level pressure rather than community outrage, and on whether open, forkable pool infrastructure exists in advance of the emergency that would require it. Positions on Stratum V2/template decentralization split even among those who agree pools are the choke point.

Common misstatements: "Mining is centralized because pools are" (conflates hash-power ownership with block construction). "A 51% pool means immediate theft" (it enables reorgs and censorship, not seizure of arbitrary coins). "Decentralized pools solve this today" (adoption remains marginal; the tooling exists but is not load-bearing yet).