The right way to do a protocol change is to describe the intended change to the major players and users, listen to their opinions, try to convince them, find a solution that they could all agree to (that is what 'consensus' means to normal people), then formalize the proposal, and confirm that it will be accepted by the majority of affected people. Only then post the code that will implement the change, programmed to be activated at a fixed block number, a couple months in the future.
That is what Gavin and Mike did.
The current controversy proves you wrong.
BTW it is not only the miners (75% of them) that decide! A valid solution might be that > 75% of the miners will mine BXT but > 75% of the users keep using BTC. This is the outcome if you have
no consensus!