What's everyone's obsession with having 4 or more closers? I've never won a league with that much cheese... a good starter is far more valuable.
Depending on the parameters of your league, having 4 closers can be a very effective strategy.
In a 4X4 league using ERA, WHP Saves and Wins, Quality closers can greatly help you in 3 categories, and also get you the occasional win. Starters will almost never get you a save.
Heck, a guy like K-Rod will even help in Ks in 5X5 leagues.
Its a lot easier to dominate in Saves , ERA and WHP , than WINS ERA and WHP because of the smaller number of innings. You can use cheaper SPs on losing teams with good WHP and ERA to make your league minimum IP---then pick up lights out RPs like Neshek,Zumaya, Shields etc. to keep grinding out ERA and WHP for the rest of the year.
Also, after 3 years of fantasy , Ive noticed that WINS are the most unpredictable category. There are only 30 closers in baseball. In a 10 team fantasy league 4 healthy closers will guarantee you near the top in Saves. Meanwhile, eventhe best SPs win total can be totally screwed by their teams Bullpen. It always seems that the WINS category is still up for grabs in September.
Your SPs fantasy value is directly linked to the rest of the Bullpen on his major league team. Closers are always in control of their own destiny.