You trying to assert that miners don't know their own business and their own hashing capabilities?   They might not know exactly in a granular way, but they should have a pretty sense about how much hashpower they are using and how such hashing power is currently allocated and how much they can ramp up more hashpower if they need to (or want to) and how much they are ready, willing and able to divert from one project to another.

They might not know exactly what others have, but they likely have a better sense than folks who are not daily engaged in such mining business.  Most sophisticated miners are likely tracking the actual hashpower of their competitors and their allies (and comparing those trackings with claims that are made about hashpower capabilities).