On Mon, Aug 17, 2015 at 12:57 PM, Rodney Morris via bitcoin-dev <
bitcoin-dev@lists.linuxfoundation.org> wrote:

> I haven't run any statistics or simulations, but I'm concerned that the
> interplay between the random distribution of transaction arrival and the
> random distribution of block times may lead to false signals.
>

You could just take the average of all the block sizes for the last 2016
window.

If average of last 2016 > 50% of the limit, then increase by 6.25%
Otherwise, decrease by 6.25%

This means that the average would be around 50% of the limit.  This gives
margin to create larger blocks when blocks are happening slowly.

A majority of miners could force the limit upwards by creating spam but
full blocks.

It could be coupled with a hard limit that grows at whatever is seen as the
maximum reasonable.  This would be both a maximum and a minimum.

All of these schemes add state to the system.  If the schedule is
predictable, then you can check determine the maximum block size purely
from the header and coinbase.