It can be.
Everybody loves a finish, but being a fighter who normally finishes fights.. he can prove to people that he can go say, 25 minutes and win dominantly. I think it could be good for your career, it shows that you can do 5 rounds and still win and that you don't only rely on finishing the fight quickly.
Like Jose Aldo said, it's good to go to a decision sometimes so you can showcase all of your skills and prove that you can still win after a 25 minute fight instead of finishing them brutally.
If we're talking about Georges St. Pierre, it would be nice to see a finish, and even though I'm not a big fan of his style, the fact he goes 25 minutes and often just dominates his opponent and makes them look so amateur is pretty amazing.
Honestly, I prefer to see fights that go to a decision instead of a finish. I like long fights, I prefer them to be exciting, back-and-forth, and a good showcase of technique more than a knock out in the first round.
I also really like to watch two high level jiu-jitsu guys roll for 15-25 minutes and show how high level they are, making it a good back-and-forth fight. Joe Lauzon's submission over Varner is one of the most beautiful triangles I have ever seen. The whole scramble and Joe sinking in that triangle during a transition the way he did was really refreshing to watch. It's nice to see somebody pull those kinds of things off at this level of MMA.
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