Not in Live View mode.
Live View mode is not MLU. If you are using Live View as an alternative to MLU, it is just that, an alternative.
On the surface it appears a decent one (I have been playing with it), with a couple of possible "gotchas" that I don't believe have been tested.
1) Providing power to the sensor to enable live view may generate heat, and thus create some additional noise. Until I've seen some "hard" tests proving it otherwise (which my company is currently doing) , I have to assume it does. If it does at what point does it become a problem(10 seconds 30 seconds several minutes?), does ambient air temperature affect it .. lots of questions, no answers right now other than canon claiming it doesn't. Their standard of "acceptable" may be different than mine, which is basically no additional noise is acceptable. If using it simply to substitute for MLU, so we're talking only a few seconds each time, I would guess that there is no difference unless doing numerous exposures.
2) from a mechanical and vibration perspective, Live View is not "exactly" like MLU. When the shutter is released with live view, the 1st curtain must return then open again. In MLU, that curtain is closed. The 1st curtain is now electronic, is very quiet and most likely causes virtually no vibration. However, since the entire goal of MLU is to enable the most vibration free stability of the camera, even this slight movement may have some impact. At this point I can see none, but that doesn't mean that micro detail on a very large print might be compromised using Live View instead of standard MLU. I plan on testing it, but probably on the 1DsMarkIII, since that will be my primary DSLR body.
(Yes I know .. I'm quibbling here. Just rambling thoughts going through too idle of a mind right now)