XP != learned. Also, there may be many very learned perl users who have just registered on perl monks yesterday, or the day before. As far as people who are both learned and long-time monks, just go to the Saints page. It ranks by number of writeups, and from that page you are two clicks away from accessing those writeups.
Ah, but lots of posts also != learned. If someone asked
400 questions, s/he'd end up near the top of the list.
...I think the best way to see who knows what s/he's
saying is to just lurk and read.