What if the blocksize limit were chosen by each node individually? Everyone would set the minimum = send and the maximum =receive.
No that would not work at all. We'd have nodes that have differentiating chain heights which would most likely cause a lot more problems. You can already limit the amount of bandwitdh that you want to spend though (e.g. 'blocksonly' mode).
So for example I would send minimum 2 mb blocks (if full), but accept maximum 6 mb blocks.
Additionally, after some time most blocks will be above the threshold that you set so it becomes ineffective. It just delays the inevitable.
Far too large a contingent would never accept Andresen, Garzik, and the rest of those cronies as the developers.
They used to be good, but now we see them 'contribute' rarely or wrongly (e.g. 'header first mining').
I see, the pesky block format is the issue in my opinion. Because it's standardized.
If the transactions were each put arbitrarly in blocks, it would be enough to just verify their hashes to see that they are original,and then there would be no need for the block format.
It would be a very big deviation from the protocol , but it would be interesting to see an altcoin try this.
So then the block sizes would vary, and each node would verify the transaction counts in them, and pass them along eachother.