Kamilla -Why do you say "I think that you can get more info out of Vertex in synastry than composite" ... ? That's like saying forget the Composite interpretation, and although it IS difficult finding freely-available excerpts relating specifically to the Vertex in Synastry, I wouldn't go as far as to say that one "can get more info out of" one or the other.
Unless you just didn't have the time to sort of delineate between the two.
lovegoblin -
I'm hoping gremlins, elves and/or gnomes are at work trying to link us to a Vertex Composite interp table.
So far, I can try to go by what I've learned so far.
When it comes to the 7th House, I think it's one of the EASIEST to read within a COMPOSITE Chart. If you think of the Composite being a third entity based on Natal mid-points, and if you think of the 7th House as Ruling Partnership, then I think it would be an optimistic position for the Vertex to be.
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... it's better to light a candle than curse the darkness