Originally Posted by
footballfanatic
.... The better comparison is to evaluate flights out of smaller cities in your area, or out of a DL or UA hub. For example, AUS-DFW-xxx is usually much cheaper than DFW-xxx because of the competition in AUS and lack of a fortress hub there.
I think this is the key. Ex-Eu often requires an overnight stop, so consider an overnight stop at ORD and get the daytime AA flight to LHR, PE may be comfortable enough.