@tony , I did more testing and discovered the following:
assignable to assignable to toggle lock when used
mouse button chord in key stroke stream
<CapsLock> yes no yes
<keycode 57> yes no yes
<NumLock> no yes no
<keycode 83> no yes no
Yes, although I can specify a chord directly in the base layer to type Ctrl-a, if I did so for all 26 letters, I will be out of easy to type chords.
NumLock essentially doubles the available chords. Given the ability to use
<NumLock> from a chord's Key Strokes stream, I can do the following:
N 00R0 <Right Ctrl>a</Right Ctrl><NumLock>
Now Ctrl-a is simply in the Num layer. If I know how to type a then I can get to Ctrl-a easily without remembering additional chords. The final
<NumLock> takes one back to the base layer. This can be applied to GUI combos too.
<CapsLock> can perform the toggle, the subtle differences between CapsLock and Shft renders it unusable.
Does this make more sense as a reasonable use case?