Rigging a character and thinking of using one armature for all the controls and one for the deformation. One of the main reasons for this is for spline iks (cyclic dependency; not being able to handle ctrl bones and splineIk bones on same armature). Any reasons this is a bad idea? Seems cleaner to me. Would hide the deform bones so aniamtors on work with ctrls.
Will this cause problems when using linked+proxy on ctrl armature? I wouldnt think so…
Thoughts? Anyone utilise this in their own work?
This method is already done. You need to find the tutorials explaining it.
cgcookie.com did a great job explaining how to do this process. It’s found in their blender essential/foundation tutorial videos.
EDIT: I am of course talking about setting up controls on rigs.
sweet as! thanks! Yep im already almost done just suddenly wondered if i was gonna run into any unforseen issues down the line!!! 
There is a way to change the way a bone looks inside the editor window. You can make widgets for your controls.
It’s only necessary if you use techniques that would create a dependency cycle, like you said. If you’re not using splineIKs, it’s superfluous - you better make use of armature layers and groups to organize your rig.