I think this is going a little too far, plus fairly useless, punishing after the fact.. (since people will get told they shouldnt do this, hopefully.. I doubt they'll actually notice the ability has been removed, unless they node edit often.. does anyone?)

There was a suggestion recently, to disallow editing completely after a certain time period, which I find more sensible. (It won't catch all this sort of problem, of course, depending upon the time period chosen, but hopefully some.)

Since there is already an edit history, maybe allowing users to view previous versions of nodes would also discourage this, as tilly just suggested..

C.