On Fri, Dec 11, 2015 at 11:18 AM, Jorge Timón <jtimon@jtimon.cc> wrote:

> This is basically what I meant by
>
> struct hashRootStruct
> {
> uint256 hashMerkleRoot;
> uint256 hashWitnessesRoot;
> uint256 hashextendedHeader;
> }
>
> but my design doesn't calculate other_root as it appears in your tree (is
> not necessary).
>
> It is necessary to maintain compatibility with SPV nodes/wallets.

Any code that just checks merkle paths up into the block header would have
to change if the structure of the merkle tree changed to be three-headed at
the top.

If it remains a binary tree, then it doesn't need to change at all-- the
code that produces the merkle paths will just send a path that is one step
deeper.

Plus, it's just weird to have a merkle tree that isn't a binary tree.....

-- 
--
Gavin Andresen