A couple of readers recently commented that the days of "dynasties", of one team becoming so dominant that they win the Stanley Cup in three or more consecutive years, in the NHL are a thing of the past.

From the late 1940s to the early 1980s, it was rather common for one team to win the Stanley Cup three or more times in a row. The Toronto Maple Leafs did it in the late 1940s and early 1960s. The Montreal Canadiens in the late 1950s (a record five times) and late 1970s, and the New York Islanders in the early 80s.

It was even common from the early days of the NHL to late 1990s for teams to win the Cup in two consecutive years.  Since 1967, for example, the Montreal Canadiens, Philadephia Flyers, Edmonton Oilers, Pittsburgh Penguins and Detroit Red Wings accomplished this feat.

Yet there's been no consecutive Cup winners since the Red Wings in 1997 and 1998, let alone any team winning the Cup as a "true dynasty" in three straight years.  It's become increasingly difficult for teams to repeat as Stanley Cup champions.

There are several reasons for this.

The current collective bargaining agreement with a salary cap and lowered eligibility ages for free agency has made it very difficult for a team to retain a dominant roster.

The length of the NHL season is another factor. For a Stanley Cup champion or finalist, they go through training camp in early September, pre-season in late September, an 82-game schedule from early October to mid-April, and then a grueling two-month playoff from mid-April to mid-June.

For the finalists, that allows less than three months to rest and recuperate and to allow nagging injuries to heal. Players also train harder and longer in the off-season than they used to, meaning they might actually see about two-to-three weeks of actual down time in the off-season. It's an incredibly punishing toll on the human body.

There are more teams in today's NHL compared to years past, meaning the talent is spread around more evenly. It was easier for savvy general managers to build and maintain a championship roster in the days of the "Original Six", or in the days of the 12, 14, 16 and 21 team leagues.

It's still possible for an NHL team to win consecutive championships of two years, but the odds aren't as good as they used to be, and are even longer for consecutive championships of three or more years.

If there is a team that actually wins the Stanley Cup for two or three consecutive seasons in the next five years, it'll be one helluva hockey club.