One handed Emacs

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A co-worker of mine is disabled and only has use of
his right hand.  He's never used any advanced editor
so isn't already biased towards any keyboard layout
beyond basic qwerty.  Has anyone developed an Emacs
layout more convenient to learn.
The standard layout has most of the most heavily
used chords on the left hand which would make
learning Emacs quite difficult.
If it makes a difference, this is on a Windows system
and I believe he does not use the stickey keys feature.