Someone can "change" the protocol only for himself. Like you can code up a web browser with a different version of HTML, lets say HTML++. If you find a couple o

Someone can "change" the protocol only for himself. Like you can code up a web browser with a different version of HTML, lets say HTML++. If you find a couple of guys who will serve you webpages in HTML++, good for you, but this does not affect me, or the next guy who still use good old HTML. Bitcoin Foundation or some well-known economist or developer may be put out some reasons for some change and convince people to upgrade to new rules. But the ultimate decision is in hands of every individual user: miner, merchant or a regular consumer.