KRS One has stated in more recent interviews — such as this one at Rock The Bells 2010 — that he regrets this line and cringes when he looks back on it.
Years later, KRS said in an interview that this was the one lyric from his career that he regretted.
Mary Lou just had a baby someone else decapitated
Flashbacks of past raps make me so glad I made it
The first line is a lyric from Stop the Violence. This is what is meant by flashbacks of past raps.
This line is from an EPMD song (“Jane” on the Strictly Business album). DOOM uses another line from the same album as the hook to “I Hear Voices”.