I can say that outshining the OW has worked for me. But this is because the OW in my sitch showed her true colors and shattered the fantasy into a million pieces. She became angry and ugly, and I stayed calm and cool. H saw her true colors. I believe that it definitely comes down to each individual situation AND the personalities of those involved -- as well as the "type" of affair.
However, due to extenuating circumstances in my sitch, which I won't get into here, OW is still in the picture. I wanted a chance to save my M, so I've held on for dear life. Admittedly, that has taken its toll on me (it's been nearly 3 years). But I can live with that because even if I end up throwing in the towel, I will know that I did everything possible to save my M. And, I'll come out in the end as a stronger, better person. I will have no regrets. I did it my way (cue Frank here).
I read through the advice on DB when I first joined, and cried on a few shoulders, too. I have also read a ton of books but in the end took the road that was the best for ME. Confrontation was not for me. Exposing the A would not have helped (everyone found out anyway). But those approaches have helped others ... again, back to varying situations and personalities ...
I agree with Saffie that newbies should not act on advice without thinking it through. I believe the 48 hr rule -- or probably longer -- certainly applies.
The subject on what approach to take can be argued till the cows come home. Lotus is correct in saying that anyone seeking advice on the DB forums needs to consider carefully. What one person deems right for them may not be right for you. I again say it comes down to each individual and their situation.
Overall, it doesn't make getting though infidelity any easier. There are no easy roads to take, there are no magical answers or crystal balls. God, don't we wish there were...