This is where my conversation with Gavin fell apart. He was not able to acknowledge the concept of a too-high limit. His reasoning was that since the limit was only one-sided (blocks with size above it are prevented) that it couldn't be too high.
Huh what?
I am not proposing infinitely sized blocks, so I obviously acknowledge the concept of a too-high limit as being plausible.
If you want to continue the conversation, please be very explicit about what problem you think needs solving, and how whatever solution you're proposing solves that problem.
We might agree or disagree on both of those points, but we won't have a productive conversation if you can't say what problem you are trying to solve.
To summarize my position: I see one big problem that need solving:
Supporting lots (millions, eventually billions) of people transacting in Bitcoin.
Ideally at as low a cost as possible, as secure as possible, and in the most decentralized and censorship-resistant way possible.
It is hard to get consensus on HOW to solve that problem, because no solution is obviously lowest cost, most secure, and most decentralized all at the same time, and different people assign different weights to the importance of those three things.
My bias is to "get big fast" -- I think the only way Bitcoin thrives is for lots of people to use it and to be happy using it. If it is a tiny little niche thing then it is much easier for politicians or banks to smother it, paint it as "criminal money", etc. They probably can't kill it, but they sure could make life miserable enough to slow down adoption by a decade or three.
"Get big fast" has been the strategy for a few years now, ever since the project became too famous to fly under the radar of regulators or the mainstream press.
The simplest path to "get big fast" is allowing the chain to grow. All the other solutions take longer or compromise decentralization (e.g. off-chain transactions require one or more semi-trusted entities to validate those off-chain transactions). I'm listening very carefully to anybody who argues that a bigger chain will compromise security, and those concerns are why I am NOT proposing an infinite maximum block size.
There
is rough consensus that the max block size must increase. I don't think there is consensus yet on exactly HOW or WHEN.