Center and radius are correct, but the angles are wrong. Here is one more example:
pts = {{Sqrt[2], 0}, {1, -1}, {0, - Sqrt[2]}}; CircularArcThrough[pts] Graphics[{CircularArcThrough[pts], PointSize[Large], Point[pts]}, Frame -> True]
Yes it's a Bug. CircularArcThrough give wrong values circular or ellipse arc from angle Theta1 to Theta2 in Circle command.
Regards M.I
