I dont think it's hockey is overly covered. As for TSN, they basically take what they can get (hence bowling, Nascar, tennis, figureskating programs more often then any of us want to see)
With CBC really only playing canadian games - and there being more american teams then canadian, why wouldn't they cover it? Not everyone cares for canadian teams even if your from canada so it's a good $ move on their part.
all the american stations like NBC and ABC carry golf programs, the jays and raptors have their own flippin stations to say the least - not to mention the score and sportsnet cover them more closely then TSN does
TSN does a good job with the cfl - friday night football is awesome, NFL however is also ruled by the american stations.
I dunno it's just tsn trying get the most viewers with as little competition as possible.
If anything, there isnt much hockey coverage other then 2 games anight once a week from CBC and a game here and there by TSN - playoffs is what it is, every playoff in every sport is killed to the tits