Curious to learn a bit more about how Google Flights 'forces' flights.
This itinerary is $750 (at least at time of posting, in L class). It is an IAD-IST r/t, with a 20hr layover in LHR on the way there.
https://www.google.com/flights/?f=0#...ANCE;so=p;eo=e
How is Google Flights able to force this? I can't work it out on the airline sites, on ITA, Expedia, Kayak, etc.
Also, how come if you just search for IAD/WAS-IST r/t on Google Flights, it won't turn this up? Cheapest r/t shows as $838, and this one with the 20hr layover in LHR doesn't show.
Thanks.