I thought I had my new Admiral's cams sync'd pretty well, using several methods. Landmarking the cams with the limb surface. Landmarking the cables with the draw stop post at full draw. Taking the cables out of the roller guard and counting dots on the cams... .
Then I thought about the radius I was looking at, between the cables and the limbs/dots and thought," if only the radius was larger than the 2 inches or so that I'm looking at?" That's when the idea came to make a fixture that would fit precisly on the cam so that a pointer could rest on a common point (the string) , relative to both cams. It had to be repeatably accurate and adjustable. I made up a prototype and checked it on all my bows that had mirror image cams, Binary and dual. It worked very well and also showed me quickly how far off the cams were in relation to each other at brace. My Admiral that I thought was dead nutz on was actually off by 1/4 inch at the pointer, which now gives me a reading 11 inches away from the axle centerline. That's 5 times the accuracy that I normally have to work with, with a 2 inch radius.
On my Patriot and Pro 40 Dually I also got a suprise! Both were so close that I don't think I could justify going to the extra work to make them perfect,, at more than 11" radius. The last time I shot both these bows they were perfectly in sync at full draw also. It would also be easy enough to purposely to advance one cam ahead of the other if you knew where you wanted to tune your bow. With the much larger radius it is so much easier to see

Here's a pic of the first prototype