I'm just in the process of putting together the single.php file for my site and I'm having some slight problems with the excerpts.
My site was based around a Xoops system which uses an excerpt and main body of text. When transferring data across, I put the intros from Xoops into the excerpt field in the DB.
This causes the problem that in order to have single.php display my full stories from xoops I have to have a <i>the_excerpt</i> in the loop. If I do this, with new stories it displays the excerpt twice.
Obviously I could always put excerpts into the 'optional excerpt' field but this is not desirable if there is another way around it, 'cause people would forget on occasion etc.
I tried using the <i>strip_teaser</i> property of content but this doesn't seem to work in that it strips the content and not the teaser. I think I'm using it wrong.