Well, the issue is that the people picker is bound to a repeating group - so what you see in the control is two accounts separated by a semi-colon, but the actual schema is different - there are two nodes. Insert a repeating table bound to your pc:Person group and then preview your form and select multiple people and you'll see what I mean.
Out of the box, IP doesn't have any way for us to insert a repeating group via rules. You can try setting the default data to include multiple instances, or you could do this with code or qRules.