Like some cult religion that barely survives, there has always been at least one but rarely more than five or six devotees throwing the knuckleball in the big leagues... Not only can't pitchers control it, hitters can't hit it, catchers can't catch it, coaches can't coach it and most pitchers can't learn it. The perfect pitch.
Remembrance of Swings Past (ed. Bantam, 1989) - ISBN: 9780553277937