Those dates don't seem to fit with what I'm seeing on Deans profile. Looks like he's actually not been active for a while (Apr 20th) and hasn't posted since the end of March. (Note he replied to EQ on Mar 8th.)
However, this can theoretically happen. We don't update your session activity (and thus last page view date) if you make an Ajax request. Normally this is fine, as we're not really requesting a new page and we don't want to change when the system thinks you last viewed. You can get this situation though. However, I think it should be left as is, as the main place the value is used (for the user) is in the what's new section, and I don't want to trounce over the value when the person hasn't actually viewed a page.