Thanks achow101 - clearly written and understood.

As a followup to my topic here: https://bitcointalk.org/index.php?topic=1771426.0;all

Let's say that 10 developers (out of 50, 70 ?) think the block should be increased from 1 MB to 2 MB (hard fork) and the reasoning behind would be that without the change or any change the network will become clogged and less reliable (transactions not going through) - I think the amount of unconfirmed volume proves it at least to some degree.

So what happens then? This is clearly an issue that needs to be addressed somehow and somebody from the 10 developers do the change in the code from 1 MB to 2 MB, commits it and then on technical level what happens? It's going to be rejected/reversed because there was no voting among miners? If I remember correctly there was a time where block size was in free float and no limit existed - but back then I believe Satoshi himself did the change.

Since which BIP miners had to vote on any change to the code? What if there was a flaw found in the code?