Math should decide the max block size, not humans (miners in this case). The goal of Block75 is to manage the max block size without any human intervention.

Under Block75, miners don't have any direct control but could still choose to mine smaller blocks (same as now), though doing so would cost them the fees from transactions they didn't include in their blocks.

A maximum block size is necessary to prevent a single nefarious miner from creating a ridiculously large block which would break the network.

- t.k.

On Mon, Jan 2, 2017 at 2:01 PM, Tom Zander <tomz@freedommail.ch> wrote:
On Monday, 2 January 2017 13:04:37 CET t. khan via bitcoin-dev wrote:
> Thoughts?

This proposal doesn't change the block size, it only changes the maximum
block size. Which is expected, nothing bad there.

The direct consequence of this, though is that the miners set the maximum
block size. Because they decide on the actual created block size.

This leads me to the simple question why we can't just give the miners full
control of the maximum block size directly?

The fact of the matter is that miners have for the full history of Bitcoin
been able to set the block size, until they hit the 1MB limit.
And your proposal keeps that property, but why have a maximum in the
protocol?
--
Tom Zander
Blog: https://zander.github.io
Vlog: https://vimeo.com/channels/tomscryptochannel