Character Classes

[ThomasCoon]

It's all very wonderful to think about and I wish I understood what it means.

I agree with you there. At this point I am thoroughly confused. Especially now that I've seen Marco's work.

In many words (but certainly not all), it seems:
<Sh> can substitute for <ch>
<l> can substitute for <r> (or at least changing <r> for <l> still creates a valid word)
<y> can substitute for <o>
<o> can substitute for <a>
And the 4 gallows can often substitute for each other.

These 21 strings are all valid (disregarding spaces):

otchord
otchold
ytchold
ytchord
okchord
okchold
ykchold
ykchord
okchald
okchard
ykchald
otShold
okShord
okShold
ykShold
opchord
opchold
opchald
ypchord
ypchold
ofShold

EDIT: opchard does not appear, as I previously claimed.