I just looked through that episode’s subtitles. The minimum duration is exactly 1.00 second. While that might not seem like enough time, its only 7 words max, while most have only a few words. Reading impairment aside, that should be plenty of time. Don’t vocalize the words in your head, it’ll help you read much faster.
Without line breaks it’s tiresome, especially with the long sentences with your eyes having to move all the way across the screen. Viki volunteers usually leave plenty of time, so it’s easy to read at a nonchalant pace.