I had this aspect with someone concerning synastry. In his natal chart, he had a Mars in Capricorn within the Tweflth House cusping the First House, how he demonstrated his Mars placement was more subtle than overt and he had the tendency to call out orders and taking the leadership position more often than not. We met over an internet gaming site, and I was still able to sense that part of himself. Even others have complained to me that he was a tad bit bossy, but he wasn't overbearing, demanding or annoying either.
His Mars by degree, closely conjunct my Capricorn ascendant, but synastry-wise his Mars placement was in my Twelfth House. We hardly argued really, and I didn't take his nature of assertiveness like it slighted me or whatever. He also didn't like my way of joking around at times.
I've heard somewhere in a few Astrology cookbook websites writing up on this synastry aspect, describe the Ascendant person of the synastry aspect more likely to approach or notice the Mars person first, than the other way around. And that's what I did, I did call out to him first for a bit of idle chit chat.