They had about one workshop per month and I traveled in Sweden, to Kopenhagen and Brussel to participate. During that year 2004, we were working on the most of the movements I have seen other teachers introduce us later on. This inverted boleo is the latest one to come up.
Ordinary boleos are always going towards the standing leg and the turning point is on the other side of the standing leg or around it as for front boleos. Inverted boleos are instead going away from the standing leg and the turning point is in the air.
I have seen it performed only by follower's right leg. The first one is in the begining of Vincents and Marylines performance in Brussel festival 2007. About 6 s in the video, the first thing after the walk.
The first time to see this boleo performed by another couple was Sebastian and Marianas milonga. Well done in both cases!
The first serie starts with an ordinary back boleo with left leg going to the right and then a inverted boleo with right leg going to the right too. The last two are ordinary back boleos with left leg.
(This link takes you directly to the steps http://youtu.be/IXkGanrd4HM?t=45s)
Here we have a double boleo with the right leg. Mariana starts with an ordinary back boleo and then continues to an inverted boleo. Beautifully done!
(This link takes you directly to the steps http://youtu.be/IXkGanrd4HM?t=53s)
And here you have the entire video!