Thank you so so so much for translating until the end. This is a true masterpiece (and to me, Fujita's best work). For all its flaws, it has a grandeur which is unmatched, and as such it stands on a league all its own (despite Ushio and Tora and Souboutei being masterpieces on their own right)...
No, it's pretty well documented that until the late Middle-Ages people used to mumble while reading or just plain read out loud so that illiterate people could understand. The practice of silent reading is pretty much exclusively a Modern one, and especially only after the space between words...