Question:
What happens when there are duplicate Participants within the same Participant(M) TouchPoint Response and they are merged together?

Answer:
The Participant(M) TouchPoint allows for more than one Participant to have a response recorded against them. When a Participant(M) TouchPoint has duplicate Participants within the same response, the Participants can still be merged.

Post-Merge, the Participant that was chosen as the master record will have duplicate responses within the TouchPoint. The user is able to edit the TouchPoint response and delete one of the duplicate records. 

This is expected behavior.