Multitasking: Mating Hoverflies

I've already documented an adult female hoverfly, Toxomerus geminatus, resting on a hydrangea leaf. The other day I found several mating couples of another common species, Toxomerus marginatus--in flight! How can they mate and fly at the same time? The male holds the female with his legs and uses his wings to keep them both in the air. It's actually pretty efficient for staying safe, but I'll tell you, it makes it doubly hard for me to get a crisp photo!

References:
http://bugguide.net/node/view/8221
http://nathistoc.bio.uci.edu/diptera/Toxomerus.htm
http://eol.org/pages/750927/overview
http://www.fnanaturesearch.org/index.php?option=com_naturesearch&task=view&id=1147