Poitier would listen to broadcasts and repeat what he heard. He would try to shape his mouth and his tongue and the placement of his vowels to match the sounds coming from the speaker. He would try out phrases, alone, and listen to his own voice, and try again. This is not unusual practice for someone working on an accent, but it requires a specific quality of ear and a specific quality of patience to do effectively without a teacher correcting you when you’re wrong.
He was teaching himself to speak American English through imitation alone, without feedback, without confirmation that what he heard in his own voice matched what he was trying to produce. That he succeeded as well as he did — that within a relatively short period his accent had shifted enough that he could audition at the ANT and be taken seriously — is evidence of both his aptitude and his discipline.
The reading lessons with the waiter operated differently but in parallel. Where the radio gave him sound, the newspaper gave him text. Where the radio gave him American English as it was spoken, the newspaper gave him American English as it was written. The waiter’s instruction in punctuation and syllabification gave him the machinery to decode text at speed, to not be slowed to a crawl by words he had to puzzle out letter by letter.
The two streams converged: the voice he was building through radio listening and the reading fluency he was building through the nightly newspaper sessions were both feeding toward the same eventual capacity — the ability to pick up a script, read it fluently, internalize it, and then speak it in performance without the seams of effort showing.