It depends. If the intention of the item is to have a general review of common property, in order to identify issues that require further investigation, then the broad brush approach is fine. But if the agenda simply says “common property” when the intention is clearly to discuss a specific issue, and perhaps one that the secretary doesn’t want to alert other owners to, then you could say it was in breach.
What can you do about it? Not a lot. The tribunal is not going to declare the decisions taken at a meeting invalid because the agenda wasn’t up to scratch. But the owners at a general meeting can do so. And that is your safety net – self policing by a majority of owners.
It it’s egregious and systemic, you can ask the owners and, failing that, the Tribunal to remove the offending committee members.