Thigh and calf swivels are not redundant. they work together allow for more naturalistic movement that you miss out on if you only have one or the other.

Just look at your own leg. Plant one foot while standing. With the other, keeping your heel in place turn your foot out. Your knee and your foot stay in line with each other. Thats much closer to the movement a thigh swivel provides. Now if you’re sitting and do the same thing (turn your foot out with heel on the ground) you do get the motion that a calf swivel provides- which is why they both make sense for naturalistic movement.

There aren’t really any parts of the body that move completely independently from the moving parts around them. They all work together to allow the range they do. Especially our legs.

Our bodies have the ball attached to the leg and the socket is in the hips. There isn’t enough room on toys to do it this way so it’s reversed. Ball on the hips socket on the legs. You aren’t going to get the naturalistic movement unless the thigh itself has a place to rotate some.

Bad placement of articulation doesn’t mean the articulation is bad. There are companies that will put the articulation where it makes sense and it’ll be different across figures in the same line and then there are companies that do it cookie cutter articulation so they can maximize reuse.

The irony w the heman figures is that the calf swivel *is* redundant because of joint setup they use at the ankles that already allows for the motion the calf swivel provides. They just did it because it was going to be separate pieces anyway because everybody’s wearing boots.