Of course users would converge on a BIP...
What annoys me and confuses a lot of people is this "emergent consensus".
Some people, Peter R in particular, make it sound as if setting individual limit on nodes somehow magically makes consensus to emerge.
When in reality it's the good old "everybody agrees first, then sets their limit to the exact same value" consensus.
The only difference is that setting the limit is now even less reliable than the soft fork.