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In a feature discussing the disappearance of the traditional rhyme book, music producer Clark Kent told XXL that The Notorious B.I.G. learned the technique of not writing rhymes down from Jay-Z.

According to Kent, The Notorious B.I.G., who would also become known for composing rhymes in his head, learned the technique from Jay-Z during the making of “Brooklyn’s Finest,” their duet on Jay-Z’s 1996 album, Reasonable Doubt. When Kent brought B.I.G. by Manhattan’s D&D Studios to get on the track, Jay-Z jumped into the booth and redid the song with lyrics that left space for B.I.G.’s verses. Jay then looked at his Brooklyn counterpart. “You ready?” he asked, pushing a pad toward B.I.G. “Your turn.” B.I.G., who had been in the practice of writing out his lyrics up to that point, declined the notebook and opted to record his parts at a later time. “The face on Big was like, ‘What? Are you serious?’” says Kent. “It was a really serious revelation moment.”

This seems to go against what DJ Premier told XXL for their "The Making of 'Ready to Die'" article. The following passage comes from the article's section about the record "Unbelievable."

I was telling him, “Dawg, I don’t know what to give you, because if I do something for you, it’s gotta be bananas.” He said, “Man, I don’t care if you take ‘Impeach The President.’ Take that and do a beat.” I said, “Really, you serious?” He said, “Hell yeah!” I went and got [the Honeydrippers’ breakbeat classic] “Impeach The President,” took the snare and kick and chopped it up, and started playing those little sounds. I wanted [to make] something more hardcore, ’cause he had played me “Warning” and stuff like that. I wanted to make something that was equally as hard or better. And he was like, “Nah, keep playing them little buttons you pushing and change it up and make it do different melodies on the hook and stuff.” He sat there a while and went in there and did the vocals. I never saw him write nothing. He’d be like, Let me get a pen and a pad—and then he wouldn’t write s***. Might scribble little funny objects or something. That was it.