<<i don't see how feminist (in general) can speak out against domestic abuse, which implies men's physical advantage in strength over women, while at the same time want to promote letting women do physically strenous work.>>
No one is speaking about physical "advantages" here. The ability to function in a particular setting or job is. Women if they were so inclined and are push far enough WILL demonstrate their strength with in the area of domestic violence( burning beds, frying pans when abuser has passed out.....)
Your comment really is immature and erroneous.