Tail and dolly: watch out!

Last weekend I was flying the Dutch Flatlands, a towing comp. The organizers preferred dolly take-offs above foot launches. Personnaly I like foot launches, especially with my Aeros with tail. I don't want to break the tail on the dolly or get stuck with it on the dolly during take-off. So I had a good look on the geometry and had the keel position on the dolly placed as low as possible. This to make sure that the tail would rise significantly before taking off. You can see that I had quite an angle:


As I was very cautious on the first launch, I held on to the dolly quite long and took it off the ground while launching. The result was that the tail was well clear of the dolly:


This was confirmed by people watching my launch. I had asked them to pay attention to the position of the tail. My second launch I was more at ease with it, because of this. The result was that I released when I felt sure that the glider was going to fly, instead of having a big speed margin to make sure the tail was well up. The result is that the tail probably came very close to the dolly (there's already forward movement compared to the dolly):


Who has already done a large number of dolly starts with a tail? Anyone else with experience regarding this topic? Any suggestions to make sure the tail will never hit the dolly?