Also, I'm pretty sure that your idea will create total chaos. Not less forks, but more. Lots more. Like on nearly every block. Not at first, necessarily, but as the subsidy shrinks relative to the transaction fees for sure.
Did I say it will create less forks? I predict that the equilibrium found will be less than 10 minutes, which means more forks.
I doubt it will be "on nearly every block". As I explained, if it comes to that, miners will choose a larger weight which decreases their invalid rate.
Actually, miners will choose the weight based on whether they got the last block or not, and whether they are getting paid kickbacks to support/override blocks from the previous miner. For most miners, I think the best payoff would be prevDifficulty+1, except when they are working on extending their own block, in which case it would be the minimum, or close to it. The exact game theory optimum would depend the acceptable range.
As I said, honest miners will build on the longest (most difficult) branch they know. This is a Nash equilibrium - a miner will want to build on the longest branch, as that improves the chances that their own block will be accepted. Increasing the weight decreases the probability that their block will be rejected in a conflict.
You sure about that? No one will ever want to ignore an easy block and try to replace it with their own hard block?
Are
you sure able that? If we assume that average block times are going to tend to be very quick, it'd be stupid to ignore
any block. This assumes, of course, 2*minimum weight > 1*maximum weight. With that, if
any weight block is added to the block you are ignoring, you lose. In fact, assuming that lower weight blocks put a portion of the fees from the block forward to the next block, it would be in every miner's benefit to mine on the low-weight block.
As for why this dynamic wouldn't just push people to mine on the lowest-weight block released, that's because, generally, people wouldn't want forks. Not to mention, we could have it so that when miners are able to spend their coins depends on weight, meaning that a building on a higher weight block would result in getting paid sooner.
Woah, multiple dynamics are going on there...