Personally I think not. If the concern is spurious bumping then simply stop bumping the post after some arbitrary edit.
This site might be part-Wiki, part-Q&A but I think its clear that people feel a sense of ownership over their questions and answers, which CW diminishes to some respect.
The question is: does this happen enough such that people won't maintain their posts as the facts change? I suspect it does.
Edit: Let me just add that there are plenty of ways of bumping your post without editing it currently, such as:
- Retagging the question (assuming you wrote an answer);
- Editing the question (assuming you wrote an answer);
- Editing someone else's answer;
- Adding another answer to the question;
- Using a sock puppet to add another answer.
- Have a sock puppet edit it's own answer.
- Have a sock puppet edit someone else's answer (provided it has enough rep).
- Have a sock puppet edit the question/tags (provided it has enough rep, or owns the question).
AFAIK all of these things will bump the question to the front page and none of them involves editing your post. So if someone wanted to constantly bump a question they already can. I haven't seen a problem like this to date, which suggest to me that we don't have a problem with spurious bumping.