We used the IAS in both of my daughter's skips (in two different school systems). The criteria and scoring are the exact same. If anything, the second can be easier because you'll likely have a larger body of evidence to look at; you'll be more experienced in the process; and, assuming the first was a success, you can say that it already worked once.
Depending on your child and when the first skip occurred, a need for a second skip should not be that surprising. If your kid can cover 4 years of material in 3 (or 3 in 2), then you'll easily be looking at two skips.
-S.F.
Last edited by SFrog; 04/16/12 10:49 AM. Reason: grammar