If you're only testing the glass, then you're only testing the GLASS. In this test, the OP doesn't care about IS or shooting situations.
However, it sounds disappointing because Canon says this: "In its latest incarnation, the '100 Macro' joins Canon's esteemed 'L'-series, and as such is held to a higher level of resolving power..."
"Higher level of resolving power."
So much for that, but it has IS, maybe less CA, better bokeh/color, fast focusing, better build quality etc. That's what makes an "L" lens, not so much it's advantage of optical quality over the cheaper versions (the 50 1.2L is NOT sharper than the cheap 50 f/1.4 at f/2.8 and smaller, and the f/1.0L is even worse... and super expensive).
I think the Leica 100mm APO is still the best because of it's lack of CA, and consistency throughout all apertures, despite not being able to go to 1:1.