Grouping like parts takes most of the guesswork out when meshing parts together.
I will be first to admit that I will try oddball parts with other components. The risk is that you may create a dysfunction with the operation/use that you the installer might only be able to address or is willing to deal with.
The cable pull ratio between road & mountain bicycle parts is an experience I can say I've had to address. The fix for it in the end was just going with the specific category for the intended parts.
Did I know what I was getting myself into? Somewhat, but not entirely at that time. I did take some good information away in doing the trial & error.
If you can risk the effort, time, costs, & all else that comes with trying out things, why not give it a shot? Otherwise, stay with the cookie cutter design of group sets.
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