@simontatham : in French, we have a lot of "homonyms": completely different words, different meaning, different spelling but same pronunciation.
When proofreading myself, I often found that I replaced a word by its homonym, even if the spelling is more complex.
Which means that when I touchtype, I do it based on internal dictation to myself and that I automatically "hear" the word before transcribing them.
Which is weird as I’m a very visual person and I "see" words in my heads when writing