The polar chart for the CK61s show the peaks and valleys by frequency from 60 degrees to 90 degrees off axis clearly. Since the mics' polar patterns vary in sensitivity by frequency off axis, and don't vary directly on axis, using this for an industry standard way to measure is really the only fair way to do it. It's similar to the way audio amplifier manufacturers use dummy loads to test and establish the amp's power output specs to simulate the resistance of a loudspeaker's voice coil, rather than using actual loudspeakers so consumers have some kind of apples to apples measurement to compare with.
It doesn't help that the distance using in measurement sometimes differs. I swear between neumann and schoeps (or someone else) they use a different distance. Might be beyer, I can't remember, but I distinctly trying to reconcile the difference in distance in comparing plots which aggravated me.
I will say that I always liked the M160 ribbons and the M88s I used on occasion back in the '80s taping the Dead, and think the 930s are a great value for the price, no question.
Thats how I look at it. I
could get closer to the sound I want, but I'd have to spend a shit ton more money to do it and it's not that big of a difference for me to care at this point in my life.