The rub with any rule of thumb is it can become entrenched belief without being challenged.
There is suspense hanging in the air over what the Edmonton Oilers will do with the No. 1 overall choice in Friday's NHL draft. They could apply the KISS principle and draft Nail Yakupov, the best player available (at least in the non-ACL surgery division), make a trade or take a defenceman such as the quietly efficient Ryan Murray. (Is it worth pointing out the fun fact that Murray, who was measured at 6-foot-½ at the NHL combine, goes first on Friday, he would be the shortest defenceman taken No. 1 overall in almost 40 years? Or that teams can find their defensive linchpin through other means besides a lottery pick?)
So the bromide about defencemen taking longer to mature until full-time NHLers is getting a lot of play this week. As one scout put it to Sportsnet's Gare Joyce: "It takes defenceman longer simply because of physical maturity."
Does it hold up to scrutiny, though? From Eric Duhatschek:
In terms of its overall makeup, the 2012 draft class bears some resemblance to 2008, which also featured one consensus all-world forward at the top — Steven Stamkos — plus a lot of quality on the blueline.
Four years after the fact, virtually every young defenceman making an impact in the NHL came from that star-studded 2008 draft: Drew Doughty, Alex Pietrangelo, Tyler Myers, Erik Karlsson, Jake Gardiner, Michael Del Zotto, John Carlson.
... [O]f the 16 forwards taken in the first round in 2008, most are still trying to find their way and are lagging far behind their defensive counterparts — Nikita Filatov, Colin Wilson, Mikkel Boedker, Kyle Beach, Zach Boychuk, Joe Colborne, Mattias Tedenby, Greg Nemisz, Viktor Tikhonov, Daulton Leveille.
Maybe it's a function of how the NHL changed postlockout and put a premium on defencemen who can move the puck as opposed to moving out the man, but the reality is, in recent years, high-end defencemen have made the adjustment to the NHL as quickly, or even more quickly, than the forwards. (Globe & Mail)
The best way to corroborate this is probably not to point out that more centres and wings taken in recent drafts have become NHL regulars than defencemen. More forwards go in the first 5-10 picks of the draft, so they probably have higher early expectations. Generally speaking, the kids on the blue line have been all right. Here's a quick and dirty and look at the drafts since the 2008's bumper crop of back-enders:
2009: A dozen defenders went in the first round — a total that might be topped on Friday in Pittsburgh. Each one has played a NHL game, thanks to the New York Islanders getting former Oshawa Generals captain Calvin de Haan into one game this season. Victor Hedman and Oliver Ekman-Larsson are each maturing into minute-munching mainstays with the Tampa Bay Lightning and Phoenix Coyotes, respectively. Neither looks like a superstar, though. Dmitry Kulikov (14th overall) also played top-four minutes for a Stanley Cup playoff team this season with the Florida Panthers.
The first Canadian defenceman off the board, former Windsor Spitfires captain Ryan Ellis, debuted this season with the Nashville Predators. There's a small asterisk on Ellis since the Predators prefer to move prospects along carefully. Ellis got into 35 games total with the Preds. That was three more than the 20-year-old Shea Weber, one of those franchise defencemen taken in a later round, did in 2005-06.
2010: Three of the first six D-men taken, the Florida Panthers' Erik Gudbranson (No. 3 overall), Anaheim Ducks' Cam Fowler (No. 12) and Carolina Hurricanes' Justin Faulk (No. 37), made the NHL as teens. Phoenix Coyotes prospect Brandon Gormley, the third defender taken in that first round, was a world junior tournament all-star and led the Shawinigan Cataractes to the 2012 MasterCard Cup. It's possible he might have advanced to the NHL with another organization that wasn't as deep as the Coyotes.
2011: It is obviously too early to tell but New Jersey Devils selection Adam Larsson, the only defenceman called among the first eight picks, made the NHL to stay this season. The next defenceman taken, Dougie Hamilton (No. 9 to the Boston Bruins), could push for a roster spot this season, depending on what happens with the NHL CBA.
Three of the four draft picks who stayed up are forwards. That includes the top two picks, Ryan Nugent-Hopkins and eventual Calder Trophy winner Gabriel Landeskog. Seven of the eight who played NHL games play up front, but it's about quality, not quantity.
Neate Sager is a writer for Yahoo! Canada Sports. Contact him at firstname.lastname@example.org and follow him on Twitter @neatebuzzthenet.