Ahh the joys of substitution
I once did something similar but at a much lower level in the pre-word days.
I reprogrammed the keyboard mapping on boot, so that some letters were whole verbs and others nouns and then joining words like and and the and a.
So someone would type in 'the' and would get something like 'yabbie pumps anonymous', someone would type a sentence and look up to see 'what you enjoy are yabbie pumps after dark with goat hampsters'
They never caught me.