"get em off of your shoulders and up around your ears, the sound of your tapes will be greatly improved"
It seems most people want the mics up higher to cut down on crowd chatter and crowd absorption. I wasn't willing to dedicate myself to that method this past weekend because of the need to turn into a 'statue' when taping that way. With the mics on my shoulders, I was able to look around, and even dance in place just a little bit, with no negative effect on the recording. I did, however, manage to get in a spot where there were no people directly around me that were talking. I was right in front of the soundboard too, and would have probably been picked out as a stealther if I wasn't able to look around like I did. I guess using omnis around your ears would allow you to move a little without negative effects, but with cards I would think you would have to be the 'statue' if they were mounted near your ears. Cards on the shoulders may not be any better either, as far as allowing movement. I think I will continue to use omnis on my shoulders because I can't hide the mics in my hair, I don't want to wear glasses with croakies, I don't want to wear a hoody or cap, I wan't to look around the crowd a little, etc. I also believe that I would appear more 'stealth' to management / sound crew than someone standing near me with mics mounted near their ears.
Your right though, increasing the height and stability of the mics can only improve the recording.