You are spot on Asa, to always use a remote release or self timer on tripod is really good advice
.
My Nikon D300 has a serious design flaw in live view as it slams the mirror down before taking the image. So one needs to exit live view and use the mirror lock up to get a really sharp image
. I do think this has been improved in later models, probably even the entry models to some extent, but I'm not up to date with newer cameras. In addition on the D300 when you magnify in live view you are actually only magnifying the small preview image, which while useful, isn't as good as it could have been if one would have been able to zoom in on the actual pixels
. So for these reasons I don't use live view as much as I would have. But such is life and things move on and improve. Seems like the newer Pentax has some nice functions to assist focus
.