[wyattk]

The problem of defencemen getting plastered was not just the trapezoid. A lot of it had to do with the way icing worked. It used to be the d-man had to "touch" the puck for it to be icing, this always resulted in d-men and forwards going nearly full speed after the puck to either get the icing call or to beat it out.

The NHL has done away with this and has "no touch icing" where the d-man only has to skate to the hash marks (middle of the circles), that's removed a considerable amount of the high-speed collisions

[yeswecatan]

Well sure, no touch is much safer, but the introduction of the trapezoid still made things much more dangerous. Icing worked the same way before and after (until a couple years ago) 2005. You didn't have defensemen getting drilled as often before 2005. No touch icing was introduced because the rule changes in 2005 made the game faster and more dangerous.