Well. wiring instructions for 30 drives?! All drives have optoisolator inputs, there is not even 30 possible variations of connections.
So documenting connection for 30 drives is a big redundancy in documentation which probably makes the documentation long with lots of parts useless for the avarage user and then too long to find things in it.
The documentation of the UCCNC is really more technical. it gives general diagrams which makes the documentation short but useful because all required information is still there to connect any type and kind of drives.
Exact connection information is probably the best for dummies, but with an avarage IQ which is required to build a machine or a controller or any technical things like a CNC machine I think anybody can put these things together from general info to exact info.
Yes you have to think a bit, but it does not hurt does it?
Dual drive: 2 pages for what? You just select the slave axis for the master axis in the UCCNC and that's all you need to do, you have dual/slaved axis. Maybe it is just overcomplicated in the Centroid if it needs 2 pages of documentation.
In the UCCNC everything is freely configurable you can put any axis or any signals to any pins so exact wiring is not the best, because the possible connection variations is about infinite.
What I wrote is only my 2 cents, please do not get offended by it. I know everybody is different and think different. This is how I see it. others might see it different.