Here is a pio sim of co open and a tight/reasonable btn cc range:
Sim constraints:
CO opening range 26.4% (RFI in CO @ 200z is 25% on my sample
BTN cc ~9% (CC% in 200z is probably a little higher than this but should be dece approx.)
Here is correct CO response OTF (100% check). This is due to the fact the btn has a condensed range with a lot of strong hands (77/55/22). The OOP wants to protect his checking range a lot here and try to get as many hands to showdown as possible, basically.
So, let us take a look at a nodelocked BTN response vs a CO 60% c-bet.
CO 60% c-bet below
BTN response vs CO 60% c-bet
CO response vs btn raise (lots of calling/raising); CO is defending some high card stuff here without flush draws like AK, AQ, AJ, AT and realistically is never raising this much.
Let's resolve for CO nodelocked to raise less and fold more....
I nodelocked CO to fold ~4% more and raise 10% less (which is realistic, we really aren't getting 3bet here much) and all of a sudden............