This is the best way to separate honorable Power Players from the dicks. If you already hold the winning cards, then playing fairly is all that’s left.
A win is a win: there’s no need to decimate or humiliate your opponent. If your objective is to have victory – whatever the project – there can be no joy in watching your opponent (whoever they might be) fail.
Fair play still means something in business (even if it is on rare display today). There will be a day (sooner than you think) that you and your opponent cross paths. Though they will remember that you won; what they will remember far more is that you played fair.
Power Players don’t sour a win with unsportsmanlike conduct. Though John McEnroe was a great tennis player, the thing we most remember is the guy who screamed at the umpire. While Bjorn Borg was simply great.