Trying to rig fingers with both master and individual controls, but applying Distribute Rotation to controls causes them to spin

Development Character & Animation
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Hi,
I’m trying to rig fingers on a rig I’m working with and my goal is to set up two kinds of controls:

  1. Individual FK controls for each phalanx bone in each finger, this is for having more control over each finger bone when needed
  2. A “master” control for each finger that will curl the entirety of the finger, this is so I can curl fingers faster, much like in these two videos:

I figured that the best way to do this is to set up Individual FK controls first, and then a master control that will control the FK controls; otherwise if I set the master control to control the bones, the FK controls will no longer align with the bones as visible here: Imgur: The magic of the Internet

The problem I’m having is that setting up a master control to Distribute Rotation among the relevant controls causes them to spin. It works fine on bones, but not on controls.

I’ve made a simple rig for easy issue reproduction made for default SKM_Quinn_Simple that consists of the following:

  • hand_l_space null to which below controls are parented,
  • Three controls for each finger in the index finger, starting from index_01_l_ctrl, each parented to another the same way as the index finger bones,
  • index_master set to Value Type Float, with a Max value of 10.
    The rig is setup as visible here: 2 - Album on Imgur

If I set up the master control to the Rig Graph you can see below, where the Distribute Rotation node is applied to all children of the index_01_l bone, it works fine:

But if I change that to controls in the Item Array and Get Children nodes, the controls will begin to spin:

I can’t think of any reason for the controls to get stuck in a loop that results in controls spinning when the exact same setup is working fine for bones. What’s causing the spin and how do I stop it?