For some reason the media feels the need to keep reminding me that toady is the 30th anniversary of the Chappell's underarm incident. It was a while later before I was in a position to have a reaction to it, and that initial reaction would tell you a lot about my character at the time!
Now, with a more rounded view of things, I still find it interesting that the sport saw almost Hair/Murali-type incidents in response to overarm, and before that even roundarm, bowling should end up removing the underarm or overarm clause from the rules (first routinely through playing conditions, then from the Laws themselves).
The changes have gone further than they need to. The rolling or excessively bouncing ball has been made a no-ball, and this deals with the real problem with the 1981 scenario. There's no reason to take away the underarm option as well, even if it is just a relic. It's not likely to be relevant to serious cricket, but can't hurt it anyway, and to my mind provides a nice link to history that should be allowed if it ever is wanted. Sure, it doesn't really matter whether the underarm balls delivered to kids in the backyard are sanctioned by the MCC, but you might have gathered that I think about hte rules a bit more than necessary.