more cup questions

[longpig.livejournal.com]

You people must be getting sick of me... but anyway, I have another question. Now that I've trimmed the stem a bit and the cup is sitting lower, I can get a better feel for it, so to speak. I've noticed, while rooting around down there just now, that it didn't really seem to be opening. I spin it and spin it, but it still seems to be sort of compressed... the shape would be more like (if you'll excuse my ASCII):
[      ]
 |    |
  )  (
  \  /
   ||

than

[      ]
 |    |
 \    /
  \  /
   ||

Could this be the cause of my leak problem? How do I fix it?