ERA Broken Down By Starts

Below are the 2007 ERA's for the Brewer starting pitchers, broken into blocks of starts. Column one and two comprise of their first and second set of five starts. The "final column includes the balance of their starts, though June 26th (number of starts are in parenthesis):

           FIRST   SECOND      FINAL   TOTAL
Sheets      4.50     3.06    2.04(6)    3.09
Capuano     3.21     5.18    5.00(3)    4.35
Suppan      2.97     4.01    7.43(6)    4.90
Bush        6.23     6.03    3.23(5)    5.17
Vargas      2.08     4.94    5.24(5)    4.29

Probably not a good idea to formulate an opinion on a pitcher based on only a handful of starts?