I absolutely live by this strategy now. For pitchers in roto leagues it is imperitive you go by their stats per IP. Just because a pitcher isnt a closer or a starter doesnt mean they arent valuable. Last yr in the Cafe Challenge league I rode the two Minny setup men all yr. Check out this stat line:
JRincon 82IP, 11W, 2S, 106K, 2.63ERA, 1.02WHIP
JRomero 74.1, 7W, 1S, 69K, 3.51ERA, 1.33WHIP
Combined, they roughly gave me:
156.1 IP, 18 W, 3 S, 175 K, 3.05 ERA, 1.17 WHIP
.115 W/IP, .02 S/IP, 1.12 K/IP - Rincon/Romero combo
.087 W/IP, 0 S/IP, 1.16 K/IP - J Santana
Of course Santana put up much better %s, but the Minny combo's %s were nothing to sneeze at - barely over 3 ERA and a WHIP under 1.2 for roughly 150 IP - Ill take that, especially considering both players were picked up off waivers.
This is one of the most underused strategies in FBB, and I for one would love it to stay that way.