I like it. I think the majority of games would end during the 3 on 3 and in turn it would make the shootouts more rare. This would make them more exciting and not a groan fest when it's your teams 3rd shootout in 5 games.
Honestly, they could push 3 on 3 to 10 minutes and I would bet almost all games end during that time. It would end up being shorter than a 5 min OT then a shootout.
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