I guess you're right as you say there's no real need to bring in the complexities of RCS - it's just that I'm familiar with that approach as it is used in TWiki (twiki.org; one of the more advanced wiki implementation) and it works very well.
In my (standard 4.6) installation there're docs for CR as well as for ETP (took me a while to realize it meant Edit This Page :). See also http://openacs.org/doc/acs-content-repository/
Had also a quick peek in the ETP docs and that looks very usefull indeed.
BTW - Is the code Dave has somehow available?