from my recollection of Scott Young's blog and to a certain extent my personal experience, you can generally up the video speed to 1.5x-2x and retain the same a

from my recollection of Scott Young's blog and to a certain extent my personal experience, you can generally up the video speed to 1.5x-2x and retain the same amount of comprehension - people generally talk much slower than you you can understand, because it takes more effort to say something than understand it.