Purely technically, as you point out, only miners need to agree amongst themselves to use rule set B, and then only a block chain according to rule set B will be built. But, as was pointed out regularly, and as was used erroneously as an argument indicating the power of non-mining full nodes, miners will not want to alienate users. Technically, they can, but economically, they would ruin themselves, because alienating the users who sustain the market cap, and who are finally the buyers of their minted coins would kill the revenue of the miners, as they will now technically mine coins nobody wants to buy.
But an army of non-mining full nodes, in disagreement with the miners (and the users) has no power to impose its rule set, whether that rule set is a "new" one (a kind of sybil attack with an army of nodes) or the "old one" (as "guardians of immutability"). They can at most initially perturb the communication of transactions and blocks, and will in the end be ignored.
That was my point.
But an army of non-mining full nodes, in disagreement with the miners (and the users) has no power to impose its rule set, whether that rule set is a "new" one (a kind of sybil attack with an army of nodes) or the "old one" (as "guardians of immutability"). They can at most initially perturb the communication of transactions and blocks, and will in the end be ignored.
That was my point.
Glad to see the part in blue finally sunk in.
In none of my references , did I infer the users were not part of the full nodes only the miners,
The Business Users combined with their own dedicated Full Nodes to the accepted standard of compliance,
can block the miners non-compliance thru ignoring their nonstandard blocks (which prevents theft of their Personal Business Inventory) & the Economics reprisals the miners would suffer from the Business dropping BTC.
Which was my point.
I never contradicted that. My point was simply that non-mining nodes have no way to impose their rules on the system. That's all I said. That holds. In order to see the "power" or rather the absence of power of the full nodes, of course you have to "undo" them of all the other possible elements that might have power, so that these element's power is not confused and taken as a proof that it are the full nodes themselves that have this power. As such, we have to, artificially, consider full nodes that have no links with users, nor with miners. And then we see that these "naked" full nodes, even if they are in a large majority (because you fired 100 000 of them up on amazon), cannot impose their rules.
On the other hand, users, even with light weight wallets, DO impose their rules, through their decision to support, or not to support, the market cap. They don't need to run a full node themselves, they can configure their light weight wallet to connect directly to the mining nodes that run their preferred version of the rules. They do this by simply voting with their money, dumping the coins if they don't like it.
So users have power through their decisions to sustain, or not, the market cap and miners don't want to disgruntle them, because miners depend on the money spending/coin buying users to dump their coinbase on them.
All this was very clearly illustrated during the ETH/ETC split.