On Wed, Jul 22, 2015 at 4:34 PM, Tier Nolan via bitcoin-dev <
bitcoin-dev@lists.linuxfoundation.org> wrote:

> It also requires most clients to be updated to support the new address
> system.


That's the killer: introducing Yet Another Type of Bitcoin Address takes a
very long time and requires a lot of people to change their code. At least,
that was the lesson learned when we introduced P2SH addresses.

I think it's just not worth it for a very modest space savings (10 bytes,
when scriptSig+scriptPubKey is about 120 bytes), especially with the
extreme decrease in security (going from 2^160 to 2^80 to brute-force).

-- 
--
Gavin Andresen