Recently I made a reservation with what I only thought had 16 segments. In fact only had 16 flight segments.
The first AAgent claimed that sames cities (LHR/LGW, EWR/LGA/JFK, etc) as described in
https://www.aa.com/content/disclaime...ld_rules.jhtml do NOT count as a stopover, NOR an open jaw, but they DO count as a segment.
Thus if you have 16 real flights then you cannot have any of those be in connections in same cities (as this would increase the count of segments to 17).
I called back, got a different AAgent and tried to re-ticket. After a day the itn had not ticketed, the 2nd [and 3rd] AAgent also confirmed this.