ganging knobs in matrixctrl dialmode

This is one of those "hoping that there's an elegant way to do this so I don't have to do it by brute force" questions. :-)

I have a matrixctrl that I'm using in dialmode, see image below. What I'm aiming to do is to allow several of the dials to be "ganged", so that moving one will automatically move others, which I have pre-selected. I plan on selecting which dials I would like to have ganged by overlaying another matrixctrl object which will allow users to click on cells to indicate which dials they'd like to be ganged (image 2 below).

So how would you do this? The approach I'm thinking of so far is brute force, and probably slow - when knob turned, first check to see if corresponding knob is "ganged" in gang-defining matrixctrl, and then if so, going through every other cell in the dial matrixctrl, testing to see if it too is ganged, and if so, applying current dial value to it too. Ugly.

For some reason I'm thinking that some nifty Jitter matrix operation could help me here, but I'm too much of a Jitter noob to know...

Thanks in advance for any help!