Thought I'd post this link to a YM article since it mentions Raggles (the one-time Hurley 22 of our very own Narc) as the smallest ever ARC entrant who finished in 28days 13hrs in 1986.
Don't know when it happened but Narc reckons that size restrictions were first introduced to avoid entries from increasingly smaller vessels. BTW he still says he would rather repeat the experience in a Hurley than a big AWB.