What percentage of the request time is taken up by events?
Please file a JIRA issue, I can see that this causes a lot of events to be generated.
Pete, thanks for the response.
I don't have the profiler results any more, but I believe the page time was around 3-4 seconds. This was a bit of an expensive page due to the amount of data being output in a table form, and that probably also explains why the event notification was becoming noticeable in this situation. I imagine in most cases it wouldn't be a problem.
I'll enter a JIRA issue shortly.