I actually consider "snooping" ok under certain circumstances.

1. The unfaithful spouse has not done everything they can do rebulid trust with their spouse (still keeps other person around as a pet etc)
2. The unfaithful spouse has been caught lying after ageeing to reconcile.
3. The information collected is used to measure divorcebusting progress rather than to condemn the unfaithful spouse.

I think the biggest concern is that the spying will result in the betrayed spouse losing control, getting depressed, or lashing out at the betrayed spouse.

This information that was collected DID help him understand what the spouse was up to whereas the spouse wasn't being informative...she was just being evasive. It is often the case that the unfaithful spouse wants to sweep the affair under the carpet. this is NOT a good approach - its got to be dealt with.

From my reading here the affair isn't over, it has just calmed down a bit because its been exposed.

Read Shirley Paige's "Not just friends"...fabulous book.