Question: May a man teach high-level and in-depth halachah classes to women on topics relevant to them?

Short Answer: According to most poskim, this is forbidden. However, some poskim permit learning all areas of Torah to women nowadays, including in-depth learning.

Question: What are the parameters for a Yisachar-Zevulun deal?

Short Answer: Rav Moshe Feinstein zt”l held that the deal must be a true 50-50%, and that Yisachar must be a mature talmid chacham already. He also lists further requirements, as listed herein.