I also encountered the vocalising/non-vocalising thing when going into speedreading. I can supress the vocalising with a bit of conscious effort but it's not t

I also encountered the vocalising/non-vocalising thing when going into speedreading. I can supress the vocalising with a bit of conscious effort but it's not the vocalising that limits my reading speed. It's all the rest that goes on in my mind that processes the information I just read. If I'm looking for some specific words, not vocalising is helpful but if I need to remember and understand the text I'm reading, I do vocalising as that doesn't impact the rest that goes on in my mind. So I'm not a speedreader but it did help me to improve my glancing skills and if I need to I can count really fast now by visualizing the numbers turning into each other.