If I read out loud faster than certain limit the pronunciation becomes gibberish. Silent reading is much faster. OTOH when I read out loud, I focus on speech, my attention and hence understanding rate drops. So it takes even longer.
For complicated writing I sometimes even have to re read silently to understand the complete meaning.
I’m not sure tbh. It can be but often it feels I’m reading the meaning of a word and not pronouncing it in head. These can be misleading easily. Writing, yes.