It helps, midpoints are like glue. In and of themselves they mean nothing, but attach them to good synastry and they can mean a whole lot.I always revert to the basics first, look at the personal planet interactions. If you're asking about the Venus-Mars midpoint because you lack Venus to Mars connections otherwise then it is a great trigger, if there are enough connections elsewhere that are not absent.
I, personally have Venus and Mars at an almost trine (10 degree orb) so for me the midpoint, forms a grand trine and has been quite a helpful chart trigger in synastry...
No astrologer will give you a straight answer unless they see the chart ;-)
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