Please explain the point of this statement - it seems to just be confusing the debate. You are saying that it would have been entirely legal for owners to institute a league wide salary cap... without union involvement, correct? If so, you are proving my point in that the union is entirely unnecessary. Everything that was accomplished to salvage the NHL (grow league revenues) was done in spite of the union, not because of it.
So, please explain why we need a players union causing lockouts? What tangible benefits do us fans receive as a result of the NHLPA? The league could exist without the NHLPA... but not the other way around.
The word you are looking for is "collusion". The same reason why anti-poaching agreements between Silicon Valley companies are illegal. I believe 'sibiriak' is saying that without CBA and union there can be no league-wide salary cap.
NHLPA is meant to provide "tangible benefits" to its members, the NHL hockey players. Without players there is no league.