Actually, there is one instance I can remember where this happen. Years ago, one of my ventricosa had a nasty accident. There wasn't much left of the vine, so one of the cuttings was a tiny, tiny piece of stem. It took ages to root, and then the newly opened top bud died as the cut was too close to it. The second bud started to swell, and it is now the growing point. It grew really slowly, and the new growth was seedling lowers and it has since grown just like a seedling. It is still producing lowers after a couple of years. I assumed it was the huge shock it had, the fact it was such a small piece of stem, plus the fact it took nearly a year to produce its first pitcher, than made it revert.