I heard from professor Marc B. Shapiro this week that the Rogachover was the preeminent genius of the 20th Century.
Who was this Hasidic sage?
I found this story on Google from Ruby Stein:
A story about the Rogachover that I heard from R. Isaacs at Yeshivat Darche Noam. The Rogachover and the Brisker Rav learned together when they were six years old. One day the Brisker’s father came to the pair and asked "which one of you is the better learner?" The young Brisker replied. "I don’t know what to say. If I said that I’m better I’d be a ba’al giva [haughty], but if I said that he is better I’d be a lier." To which the young Rogachover responded- "You just made yourself into both!"
In regard to speed davening, two stories comes to my mind. The first is about the "Rogachover" who was a real gaon (genius) on par with the GR"A, who used to be the first to finish davening shmonah esreh (the amidah) before anyone else did. The people in the shul felt uneasy that the rav had to wait for the congregation, so they went up to him and asked him that before he takes three steps backwards (signifiying that he finished davening) maybe he could learn something (since he knew shas by heart that would not be a problem for him) and thus lengthening his davening. He replied that he already did that too.