The bitcoin protocol is doing whatever the most popular bitcoin client does. After a fork it&#x27;s the same.<p>&gt; but they&#x27;re not the same protocol in much the same way that Dogecoin is not the same protocol as Bitcoin<p>What you&#x27;re arguing is essentially that &quot;EMCA6 is not javascript because it supports features the previous javascript didn&#x27;t, much the same as ruby does&quot;.<p>Bitcoin is a cryptocurrency. They&#x27;re the same cryptocurrency both before and after the fork. Dogecoin is not. Can you see how that term is not a good term when we have a better one?<p>Also &quot;achieve consensus&quot; there is absolutely incorrect. The correct term is &quot;will have to update their software, else they will be incompatible&quot;. Software updates are normal, and we don&#x27;t demand that each program rename itself every time it updates.<p>&gt; That is not the only way to implement a fork<p>That&#x27;s the only way anyone&#x27;s trying to fork though. Yes, gavin said he&#x27;d just do a hard-cut over, but he didn&#x27;t and it&#x27;d be a bad idea.<p>Forking the chain is only useful if the economic majority and miners come along, else your chain will be less secure and less useful (also, double spending problems etc).