Vie-lhr-dfw-aus
My story:
My route was VIE-LHR-DFW-AUS on BA/AA. Layover in LHR was 70 minutes (same terminal). VIE-LHR delayed in air by about 15 minutes; I resigned myself to missing my flight.
Of course, when I land I have to try to make it. I proceed at a brisk pace: AA extra sticker security, make my way to security, step over someone who crumpled on the walking sidewalk (much to their family's amusement - she'd apparently never been on or seen a moving sidewalk, and panicked), through security, to the gate, without breaking stride once. Walked onto the plane, sat down, door closed...
Layover in Dallas was supposed to be 90 minutes. LHR-DFW delayed in air by about 40 minutes or so. resigned myself to missing my flight.
Of course, passport control/customs wasn't crowded, my luggage came off first... I proceeded at a brisk pace to continue through security, changed terminals and... walked onto plane, sat down, door closed...
It wasn't until I arrived that I realized I'd done VIE-LHR-DFW-AUS without spending a single minute waiting in the airport. I'd gone gate to gate to gate to gate to gate to gate rather continuously.