My reasoning was the sidebar on the RHS of the page: this is one of 20 or more pages on "bowling styles". I don't think any other "bowling style" page discusses a specific incident (e.g. Bodyline is not on the bouncer page). Also, someone specifically looking up the 1981 incident is confronted with (for them) irrelevant stuff on the history of underarm bowling. Also my observation is "multi-pronged" Wikipedia articles tend to expand such that a split becomes necessary sooner or later - even hough, as you say, the article isn't too long yet. Having said all that, if people don't agree with me then so be it.