&gt; No, you&#x27;ve created software that works the same now, but could cause a fork.<p>Where is the problem? As far as I understand it (but prove me wrong!) in the extreme case we&#x27;ll have two Bitcoin blockchains: One without the block size restriction and one with. In each of these two blockchains there will be a consensus (that&#x27;s what the Bitcoin protocol is in principle about). In the &quot;typical&quot; case the supporters of one of these two forks will stop mining in it, since they see that it is &quot;not mainstream enough&quot;. If both blockchains have lots of supporters behind, we&#x27;ll have &quot;two different bitcoins&quot;. Here it can get interesting, since now we have &quot;two different products&#x2F;bitcoins&quot;, where the market will have to decide (and in the extreme case this ability to choose will damage bitcoin - here also things get interesting).