Um, not quite. Reparenting is the process janitors (and a few others) use to move nodes between different threads. Since this has the effect of changing history, we try not to do it very often.
I believe you're thinking of the term editing ;-) and here's what the book of Turnstep has to say on the subject:
Why can't I edit some of my nodes anymore?
A: Most top-level nodes are not editable once you submit them. That's why there is a "Preview" button. Go over your post very well, for you will not be able to change it once you select "Submit".
What is a "top-level" node?
A: A top-level node is any node that is not a reply to someone else's node. This is usually starting a new discussion, asking a new question, posting a new piece of code, etc.
Which top-level nodes *are* editable?
A: First, here is everything that is not editable. Once you create these, you cannot change them:
- Seekers of Perl Wisdom
- Perl Monks Discussion
- Categorized Questions and Answers (both questions and answers)
Here is a list of things that can be changed once you create them:
Note: Material quoted because it's awfully far down on the node and it's far to easy to become distracted while reading the rest of the information turnstep thoughtfully collected.
(Mind you, I know you already know this, but I figured it was worth highlighting for the sake of our new initiate.)