The Taproot upgrade represents one of the most significant developments for Bitcoin’s mainchain in recent months. Despite seeing very little controversy, the community is still debating on the proper procedure on how to implement it more than six months after the BIPs were published.
The issues stem from the necessity of conducting a soft fork that would be accepted by all relevant stakeholders. According to a Reddit thread pinned in the r/Bitcoin community, “the biggest problem with activating Taproot is PTSD from the previous softfork, SegWit.”
History of SegWit
SegWit consensus in 2017 followed the BIP9 soft-fork procedure, which required 95% of all miners to signal that they upgraded to the new software and were ready to complete the fork. A time-out period existed that automatically rejected a proposal after consensus hadn’t been reached by a certain date.
The very high degree of required agreement meant that a single relatively large miner could stall the upgrade and “hold it hostage.” Allegedly, miner opposition to SegWit was due to “covert AsicBoost,” a mining enhancement technique that the upgrade would have made unusable. However, SegWit was ultimately the culmination of a community debate on block size spanning years, which was mostly resolved with the Bitcoin Cash fork.
To avoid similar controversy, two different techniques for Taproot are being proposed.
Taproot activation still far away
An alternative to BIP-9 is to codify that the upgrade will be activated after the timeout, instead of being rejected. Since this would effectively lock in the decision to fork before its activation, it is seen as a less ideal measure.
Instead, a “Modern Softfork Activation” procedure proposes a hybrid system where the upgrade would get rejected after failing to reach consensus in a year. After another six months of discussion, the community could decide to begin a two year-long procedure which would activate the upgrade at expiry. The maximum length for this procedure would be 42 months, or three years and a half.
As of right now, the timer is not yet ticking. More than six months have passed since Taproot’s initial formalization as a Bitcoin Improvement Proposal in January. Several code improvements have been pushed to it since, though they do not constitute major changes.
Taproot improves certain aspects of Bitcoin privacy related to complex spending conditions. It allows hiding the conditions that were not triggered, and can make multisig transactions look indistinguishable from single wallet transfers.
The upgrade was previously hyped up, which fueled some misconceptions on its upcoming features. Some believed that it would make the CoinJoin privacy protocol impossible to distinguish from normal transactions, though as Cointelegraph previously reported, CoinJoin is not affected at all in the final version of Taproot.
But despite the relatively uncontroversial and limited set of features, Taproot may take months — if not years — to be activated.