Like many people, I’ve been doing some language study during the lockdown. On my daily walk, I’ve been listening to a Greek course delivered entirely through audio, with no reference whatever to the written form. It remains to be seen if this has worked, since I haven’t had the opportunity use it. But one thing I can be fairly sure of is that my Greek pronunciation won’t be subject to spelling-induced error.
Learning through the eyes
Most learners of English, certainly the ones I’ve come across in my teaching career, have not learnt entirely through the ear as in my Greek experience. Most have learnt through the eyes too. They’ve used books, not just audio, and most have been both guided and misled by the written form. We shouldn’t underestimate the importance of spelling in teaching pronunciation, and not only for the productive (speech) skills but also for the receptive (listening).