I am having the same issues, and can eat a good bit (I.e. A whole Peanut Butter sandwich). I'm full for a couple of hours, then an ready to eat again! I have lost about 40 pounds, but only 20 post surgery.
I dump rather routinely, but eating too quickly most likely allows more food, and potential for dumping. Primarily a problem when I am at home, then I just shut my eyes and lay down until the nausea and dizziness are gone!
I routinely wonder if I have stretched mine out as well...
Surg date: 8/26/13; SW 257; Current weight: 217