If I were a player, its by any means necessary.
As a fan, I'm detached, I"m not on the team, I'm on the bandwagon of the experience.
And as a fan, a true fan, you ride your team through ups and downs, through those peaks and valleys. I was a proud Notre Dame fan this year when they were especially crap. It will their return to glory one day all the sweeter to know you slugged it out through the muck(I hope a return to glory). Using them as an example, its pretty apparent they didn't cheat to perform this poorly, so I wouldn't want it to turn on cheating.
But moreover, as a fan, I basically derive enjoyment on a few levels. One, the entertainment, pure entertainment of watching a team. This part of me would love to see a parade and trophy hoist, sure. But equal, if not greater elements of fandom to me, is in the inspiration of watching a team. The ups and downs of a team are a frequent mirror to the human experience. We all have good days and bad days, good months and bad months, good years and bad years. If you let bad days keep you down, you'd never get up. It is that fight that can be an inspiration.
I'm on the record as an avowed Yankee fan, but I'll tell you this true, as painful as the 2004 ALCS was(I've called Sports 9/11), I honestly took personal inspriation in the Sox story. Down 3-0, Mariano on the mound trailing in the 9th, 1918, the Curse, coming off a 19-8, 26 World Championships, Aaron Boone, Bucky Dent, Bill Buckner, the whole bit, and those boys stared down all that history and got off the mat. That loss was remarkably painful, but also remarkably inspiring, and I've called that loss a choke by the Yankees, but I truly feel thats selling those Sox short. I never wanted to see them win, but you know what, I can respect that and have thought of that in tough times. Crazy heresy I know, but its true.
Coupled with inspiration is the notion of bragging rights. You want to talk some S to your friends. That Giant run this year was all the sweeter because of the Cowboy win. That honestly felt like the Super Bowl winning that game because I roll with so many cowboy folks. Ditto the Yanks beating the Mets in baseball, Devils beating the Rangers in hockey. It doesn't mean much, but talking a little smack is fun.
Both of those experiences would be unavoidably hollow to me if my team cheated to get there. Believe me, as a Yankee fan, I was in awe of Clemens in Seattle in 2000. Probably the most dominating game I've ever seen pitched, and I've watched 7 no hitters live from the first pitch in my life. To know he did that with the aid of the juice, it makes me feel awful that those seattle players and fans got gyped of that experience. I take cold comfort in the fact that none of those series the yanks won were 7 gamers, and I'd like to think the roid effect was negliable, but that game in particular really sticks in my craw. I couldn't be proud of that game or brag about it, it feels forever tainted to me.
Cheating robs us as fans of those two great moments. Whats the point if its not on the level? I can see intellectually why you might like it, but I find it insane to think you'd dervive any true satisfaction about it as a fan.