It does sound like it's working (because you get good focus on your AF point) but that, after a maximum aperture of f/4 on your 24-105mm, you are just now learning the delights and challenges of shallow depth of field.
Also, while this lens is a good performer, as you get down to the max, f/1.4, things tend to soften a little dead center, and significantly out to the edges of the frame. And don't expect the sharpness to be perfectly symmetrical--that is, even with a great body, good AFMA, and an excellent copy of the lens, there might be one edge or corner of the frame at f/1.4 that is somewhat sharper or softer than others.
But the lens is TONS of fun, can produce awesome images when all things (exposure, composition, focus, lighting, subject) align, and is so light and convenient. I tend to use mine on a 60D and can get some very cinematic types of results.
And my AF is accurate and super-quick. I really do need to use it on my 5D3 more often, but I will admit I'm in the queue for the Sigma 50mm Art, chasing that slightly better image quality and edge to edge sharpness like a junkie chases a high (some might say...).