Correct me if I'm wrong but as I understand it the following is the bone transformation procedure:

R = current anim key rotation matrix
T = current anim key translation matrix
R1 = next anim key rotation matrix
T1 = next anim key translation matrix
G = transform matrix
G1 = parent transform matrix
I = inverse root matrix
O = bone offset matrix
F = final transform for bone

So:
G = interp(R, R1) * interp(T, T1);
F = I * G * G1 * O;

That is alot of matrix multiplications each frame. Is there anything that can be done to simplify and speed up the process?

Are there any matrices that can be "baked" / pre-transformed without causing artifacts during animation (interpolation) ?