Absolutely, yes. In my case I was annoyed that my round trip from Orbitz took me through Hong Kong for 3 hours, so I went to Flightfox to see if I could make it

Absolutely, yes. In my case I was annoyed that my round trip from Orbitz took me through Hong Kong for 3 hours, so I went to Flightfox to see if I could make it 3 days. They said yes -- AND made the flight cheaper! The other option was to try to book multiple round trips or a multi-city with Orbitz/Expedia/etc and in my case it was driving the cost way up. I wasn't happy with the result, and couldn't get the price sub-$3500 to do what I want -- and then I would have had to pay food and accomodations on top of the higher price.