How important are fieldset and legend tags in a form?
I have a form with some section headings that should (as I see it) be legends for fieldsets and also look like headings (h3 sec_main), but the W3C validator objects when I nest legend inside h3 or vice versa, putting legend inside div breaks everything, etc. And legends don't display as full-width blocks like h# or div, so putting class="sec_main" directly on legend necessitates more CSS finagling to get it wider with a larger font size.
Suggestions? I don't want to just have each heading display on the page twice so one can be a legend and the other can be styled as a heading; that would look really redundant.
Is it bad to omit the fieldsets/legends and avoid the whole problem?