its not a big dela to win one game visiting in round one
Well, historically it has been: teams who won the 1st game of 7 games series advanced 80% of the time.
I was thinking about that stat. I think it's because at least 80% of the time the team that wins game 1 is a higher seed playing at home. Therefore, when a visiting team wins in game 1 it doesn't necessarily mean the statistics are weighted in their favor all of a sudden.
The stat I'd want to see is how often a 7 seed has gone on to beat a 2 seed after winning game 1. Or if there isn't sufficient data for that, look at the frequency of a 7 beating a 2. I'm sure the numbers would be far more encouraging.