Originally Posted by alanw
US to PHL
DL to ATL and NYC
CO to EWR
SQ to SIN
TG to BKK
come to mind
SQ to SIN has a stopover in MXP. Better/quicker to go with TG BCN-BKK-XXX (final destination) rather than BCN-MXP-SIN-XXX even though you (probably) stay on the plane.