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Date: Tue, 31 Jan 2023 21:07:16 -0500
From: Peter Todd <pete@petertodd.org>
To: Christopher Allen <ChristopherA@lifewithalacrity.com>,
 Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>,
 Christopher Allen via bitcoin-dev <bitcoin-dev@lists.linuxfoundation.org>
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Subject: Re: [bitcoin-dev] Debate: 64 bytes in OP_RETURN VS taproot
	OP_FALSE	OP_IF OP_PUSH
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On January 31, 2023 7:46:32 PM EST, Christopher Allen via bitcoin-dev <bit=
coin-dev@lists=2Elinuxfoundation=2Eorg> wrote:
>All other things being equal, which is better if you need to place a
>64-bytes into the Bitcoin blockchain? A traditional OP_RETURN or a spent
>taproot transaction such as:
>
>OP_FALSE
>OP_IF
>OP_PUSH my64bytes
>OP_ENDIF

What's wrong with OpPush <data> OpDrop?

>I know that the anti-OP_RETURN folk would say =E2=80=9Cneither=2E=E2=80=
=9D But if there was
>no other choice for a particular protocol, such as a timestamp or a
>commitment, which is better? Or is there a safer place to put 64 bytes th=
at
>is more uncensorable but also does not clog UTXO space, only spent
>transaction `-txindex` space?
>
>My best guess was that the taproot method is better, but I suspect there
>might be some who disagree=2E I'd love to hear all sides=2E

An important consideration with using taproot is that you need to have the=
 data you are committing too to be able to to spend the txout in the future=
=2E OpReturn doesn't have that problem, meaning that in a situation like a =
hard drive failure, you can still recover the funds from a wallet seed=2E

Also, it is incorrect to say that OpReturn outputs "clog UTXO space"=2E Th=
e whole point of OpReturn is to standardize a way to keep such outputs out =
of the UTXO set=2E There is the 75% discount to using witness space=2E But =
considering the size of a transaction as a whole using taproot instead of O=
pReturn doesn't save much=2E

Finally, _64_ bytes is more than a mere 32 byte commitment=2E What specifi=
c use case do you actually have in mind here? Are you actually publishing d=
ata, or simply committing to data? If the latter, you can use ECC commitmen=
ts and have no extra space at all=2E