The peninsula is measured from the "connecting edge". That edge would be where it connects to the wall run of cabinets and counter. Otherwise it isn't even a peninsula, it's an island that happens to have one side or end against a wall. What the requirement is for is COUNTER use receptacles. The code is referring to the counter top in this section, so the connecting edge is where the peninsula counter connects to the other counter.
I think you are over thinking this Dennis. This is one of those things that just is what it is and 99.9 percent of people see it this way.
BTW, somebody from New York must have written the section in the code. PeninsulaR ? What the hell.