I suspect it would be troublesome: normally, the author has five minutes in which to make incidental edits after posting, during which time his modifications do not produce any new revision entries. Forcing a new revision during the salutation/punctuation-stripping could complicate this.
As an alternate solution, I would like to propose that these changes be made during the rendering stage, leaving the original source intact. This could help to reduce confusion and preserve the author's original text in the revision history, while still accomplishing the goal of reducing obvious noise.
I suspect that the solution in use right now (queries that modify the data directly) has the advantage of being fast and easy to implement. I'm not familiar with the details, but I'd wager it avoids the time/cost of having to re-render potentially hundreds of thousands of pages in response to the edits. Adding a revision would no doubt be even more costly, though implemented as a bot it could be feasible I suppose.