Lets take a look at some of the rules changes that happened during this decade.
Goaltenders allowed to pass the puck forward, up to their own blue line. Minor penalites are changed from three minutes down to two. Overtime limited to 20 minutes.
Delayed penalty rules introduced. Each team must have a minimum of four players on the ice at all times. Two rules were amended to encourage offense.
No more than two defensemen permitted to remain inside a team's own blue line when the puck has left the defensive zone. A faceoff is called for ragging the puck unless short-handed.
Goaltender's leg pads are limited to 12-inch width. Timekeepers mark the end of the period rather than the referee's whistle.
Teams are to dress a maximum of 12 players for each game with no more than 14 on the roster.
Blue lines repositioned to 60 feet from each goal line, thereby enlarging the neutral zone and standardizing distance from the blue line to goal.
To further increase offense, forward passes allowed in defending and neutral zone and the goaltender's pads are reduced from 12 to 10 inches.
Game standardized at three 20-minute periods of stop time separated by ten-minute intermissions. Teams to change ends after each period.
Ten minutes of sudden death overtime to be played if the score is tied after regulation time.
Minor penalties are to be assessed to any player other than the goaltender for deliberately picking up the puck while it is in play. A minor penalty is to be assessed for deliberately shooting the puck out of play.
The Art Ross goal nets were adopted as the official net of the NHL.
Maximum length of hockey sticks is limited to 53 inches measured from heel of blade to end of the handle. No minimum length stipulated.
Home teams given choice of which end to defend at the start of the game.
Forward passing permitted in defensive and neutral zones and into the attacking if pass receiver is in neutral zone when the pass is made. No forward passing allowed inside the attacking zone.
Minor penalties assessed to any player who passes the puck back into the defensive zone.
Ten-minute overtime without sudden death provision to be played if the game is tied after regulation time. Games tied after this overtime period declared a draw.
Exclusive to goaltenders, teams to dress at least eight players and no more than 12 skaters.
Forward passing permitted inside all three zones but not permitted across either blue lines.
No more than three players including the goaltender may remain in the defensive zone when the puck has gone up the ice.
Minor penalties to be assessed for the first two violations of this rule in a game, major penalties thereafter.
Goaltenders are forbidden to hold the puck. Pucks caught must be cleared immediately.
For infringement of this rule, a faceoff to be taken 10 feet in front of the goal with no player standing between the faceoff spot and the goal-line.
High sticking penalties are introduced.
Maximum number of players in uniform increased from 12 to 15.
December 21, 1929; Forward passing instituted at the beginning of the 1929-30 season more than doubled the number of goals scored.
Partway through the season, these rules were further amended to read "No attacking player is allowed to precede the play when entering the opposing attacking zone." This is similar to the modern day offside rule.
As you can see a lot of the rules that are part of the game today, originated during this decade. He are the top ten scorers of the 1920's.